# Misfires after changing all spark plugs and coil packs



## dainfamous (Feb 1, 2008)

Hi,

I get random misfires after changing the coil packs and spark plugs.
What else should I look into?

The car is APR stage 1 with approximated 75k miles.



Thanks.


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## bacillus (Apr 21, 2011)

Spark plugs gapped correctly?


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## TBomb (Sep 23, 2009)

bacillus said:


> Spark plugs gapped correctly?


For what it's worth, you might *check* the gap but don't try to *change* the gap, as you stand a high chance of damaging the electrode on the plug itself.

With 75K miles and fresh plugs and coil packs my guess would be intake valve deposits :thumbup: You have random misfires meaning not just one cylinder? Did it start before you changed the plugs and coil packs, or after?


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## Krieger (May 5, 2009)

missfires in which cylinders and how often?

also, at idle, wot, cruising?

bit more info.

@tbomb, that's old school thinking. You can easily change the gapping, just don't be retarded and slam a coin or something in there and start bashing away. lol


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## dainfamous (Feb 1, 2008)

Thanks for the responses.

I didn't perform the install myself.

Prior to changing the coils and plugs I gotten a misfire in one of the cylinders (thinking number #2) which caused a CEL. So I proceeded to have everything replaced (plugs and coils) for precautionary measures.

Its been 3000 miles since the change and I still get intermittent misfires not enough to cause a full blown CEL though once I did see my CEL light flashing while under WOT and disappeared after I let off the pedal.

It doesn't happen all the time. At times its smooth as butter.

Thanks.


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## YoungMedic (Mar 22, 2006)

bad fuel injector


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## Krieger (May 5, 2009)

idk about the injector there... id be more thinking along the lines of poor gap, a bad coil or plug, or carbon. injectors tend to run bad all the time if they are bad.


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## YoungMedic (Mar 22, 2006)

mine didnt, intermittent misfires on cyl# 4, replaced plugs and coils, still had misfire and cold start misfires. pulled the #4 fuel injector and found it caked with carbon. replaced injector, ran like a champion and no more cold start misfires. did this at 68k miles


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## Dabpy (May 1, 2012)

YoungMedic said:


> mine didnt, intermittent misfires on cyl# 4, replaced plugs and coils, still had misfire and cold start misfires. pulled the #4 fuel injector and found it caked with carbon. replaced injector, ran like a champion and no more cold start misfires. did this at 68k miles


How big of a job is it to pull the injector?


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## YoungMedic (Mar 22, 2006)

it wasn't too bad, if you google Stasis k04 install there is a nice step by step on how to pull the manifold. Took me about 2 hrs to pull it, and an hour to get it back together, first time. And there are specialty tools involved


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## gmikel (Nov 10, 2010)

*triple square*



YoungMedic said:


> it wasn't too bad, if you google Stasis k04 install there is a nice step by step on how to pull the manifold. Took me about 2 hrs to pull it, and an hour to get it back together, first time. And there are specialty tools involved


check the tools rquired as i forget the size of the triple square for the manifold support. don't start until you have on that is at least 4 inches long. you can't run to the store and buy one and you'll save yourself a lot of frustration. they are available at ecs and other vendors that advertise here.


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## StuMacLean (Aug 9, 2003)

Long shot theory here, but I've seen B5 S4s have oxidation on the wiring to the coil packs. My friend chased a misfire for a year before finding that the connections on the coil pack cable was oxidized. 

Could be worth taking a peak.


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## jpawl (Apr 12, 2000)

Jumping in here. 

Not much to add other than my frustration over the CEL after new plugs and coil packs. 

Check engine light at 69.5K miles. APR Stage 1 flash over the last 59K or so. 

Independant garage replaced spark plugs and coil packs and sent me on my way. CEL came back on as soon as I left. VAG-COM'd that night. Cyl 4 tripped it at a very low RPM. Reset light, same thing, cyl 4 trips it on a cold start up at low RPM (under 1800). 

I have since changed back to program 1 (stock) to see if that would help. I have the same CEL coming back. The garage is thinking that maybe a BG intake cleaning service will help clear up with what we both think is a carbon build up in the intake area due to the direct injection. I have read mixed reviews on it.

Jim


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## OEMplush1 (Jul 21, 2011)

I had flashing cel light after doing same changes, I added catch can and removed plastic PCV and my boost issues went away.


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## Weelildubb2.0t (Apr 19, 2007)

jpawl said:


> I have since changed back to program 1 (stock) to see if that would help. I have the same CEL coming back. The garage is thinking that maybe a BG intake cleaning service will help clear up with what we both think is a carbon build up in the intake area due to the direct injection. I have read mixed reviews on it.
> 
> Jim


I heard the same thing about the BG intake cleaner, if the BG service is a lot of $$$ I'll just skip it and go right to manual valve cleaning


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## rboss101 (Jan 29, 2011)

My car started experiencing misfires after changing the sparkplugs. Never happened before. Now it gives me a code for random misfires and #4 in particular. Today is the second tome it happened after starting the car on a cold morning. Second time 2 weeks after changing spark plugs. Just after I start, when its still cold, and never during driving or idling when warmed up. Strange. Could it be the plugs. I am using the new NGK ones. NGK Part # 1675 Laser Platinum pre gapped. Didnt have a problem with this before. I think these a are one range colder than the previous ones I had in the car. Could that be the problem?


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## ROH ECHT (Dec 9, 2010)

Unexplained random misfires usually turn out to be carbon build up. Not so much a prob for newer motors, but yes this happens to be the more common culprit;
I clean every 10k miles. I made a vid;

http://www.youtube.com/watch?v=ykenBjJ8XZM


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## bkpapi12 (Feb 17, 2008)

same thing happened to me after changing to red coils + new plugs. 2 cylinders with random misfire's cleared codes, squeezed connectors on coils + plus gentle tap on coils. 800 miles later cel free. hope this helps


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## ina04gli1.8t (Sep 24, 2010)

Same problem ! I threw a code, scanned it & it came up missfires on all four cylinders, The next day the cel went out but i scanned it again & got a pending code for misfire on #4. I decided i had nothing better to waste my money on so i replaced all four coilpacks with Audi R8 coilpacks & ngk plugs, started the car & could clearly hear a misfire at idle, I scanned it again & of course it came up misfire on #4. Being that it's still under warranty I will be taking it back to the dealer & hopefully they won't deny me because of all my upgrades. I cannot help but wonder why apr's K04 kit for the fsi came with injectors & a hpfp. My car has 18K miles & had numerous coilpack replacements & the hpfp has been replaced.


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## everfresh59 (Jul 26, 2010)

I'm having the same problem with a cylinder 3 misfire. I replaced the coils and plugs and no go. I'm gonna do fuel filter on the weekend, and if that doesn't work, intake valve cleaning she goes... I'll probably have my fuel injectors cleaned as well.


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## kylegti07 (Apr 4, 2012)

so i have a 07 gti that just went stage 2, 82k miles, new coils, plug are about 20k old, but just regapped to APR's .028 specification.

problem:
I keep having very small misfires, almost like little hiccups, only in 4th gear at wot...... im about to replace my external fuel filter in hopes it will help, any ideas as to what could be going wrong???


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## ohDirka (Jul 13, 2012)

kylegti07 said:


> so i have a 07 gti that just went stage 2, 82k miles, new coils, plug are about 20k old, but just regapped to APR's .028 specification.
> 
> problem:
> I keep having very small misfires, almost like little hiccups, only in 4th gear at wot...... im about to replace my external fuel filter in hopes it will help, any ideas as to what could be going wrong???


I am having the exact same issue. I have only noticed it in 4th under WOT as well. I've been thinking about doing a valve clean when I have some extra time.

Here's my mods, maybe we have something else in common. 

07 GTI 67k miles, Stage 2 APR, BSH pcv block off, AWE DV, Spark Plugs changed 10k miles ago, Cam follower changed 14k ago, oil changed every 5k, Coil packs changed at various points of failure (none of them have more than 10k on them), Fuel Filter changed 10k miles ago.


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## kylegti07 (Apr 4, 2012)

ya dude we are almost the same i have the bsh block off plate also, i just am using the stock diverter valve with the forge spacer. im going to have a buddy do logs this weekend and will report back. i did however just run a bottle of the techron fuel system cleaner through the car and i havent felt a single misfire in 3 drives again ill report back if it continues, also im about to do a seafoam cleaning so well see wat that does.


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## ohDirka (Jul 13, 2012)

So everyone that is having this issue is running an APR tune right? I also noticed this doesnt happen if I do a run from a stop. The only time that I've noticed this is when I downshift into 4th and then go WOT. Is this the same for everyone?


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## kylegti07 (Apr 4, 2012)

it only happens on mine wen i hold high rpm in fourth then go wot. if i just downshift and go wot it performs beautifully...... this to me seems like an injector issue, which im hoping its not, but who knows, im getting logged soon so ill post results


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## ohDirka (Jul 13, 2012)

I checked mine this weekend, I had a low fuel rail pressure code. 

What did yours come out to?


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## kylegti07 (Apr 4, 2012)

never got any useful codes, no cel or anything saved other than misfires, i think the guy that helped me get my code didnt know wat he was doin.....:screwy: however i think i pinpointed the cause, i think i have a boost leak at the turbo outlet to intercooler pipe, the fitting seems loose and im not sure how to tighten it up since its the oem couplers


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## ohDirka (Jul 13, 2012)

kylegti07 said:


> never got any useful codes, no cel or anything saved other than misfires, i think the guy that helped me get my code didnt know wat he was doin.....:screwy: however i think i pinpointed the cause, i think i have a boost leak at the turbo outlet to intercooler pipe, the fitting seems loose and im not sure how to tighten it up since its the oem couplers


I already replaced those on mine. If you have a leak there, just buy a new o-ring. I think it was like 6$ or something and it tightens everything back up. :thumbup:


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## kylegti07 (Apr 4, 2012)

just bought new orings and the problem still exists ughhhhh im now leaning towards the bsh block plate as the issue. also ive been trying to get a base line by running against another gti but none of my buddys are around to do pulls so im not sure if the car is making power the way it should be


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## ohDirka (Jul 13, 2012)

kylegti07 said:


> im now leaning towards the bsh block plate as the issue.


I was thinking the same thing... Maybe it is not getting a good enough seal or something. I'll probably pull it apart this weekend and check it out.


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## kylegti07 (Apr 4, 2012)

ya that or my thinking is that the oil getting blown into the exhaust my combust due to the new high temperatures the downpipe is reaching..... just a thought. i think i am gonna put on the stock pcv and if i still get the burps im going to put the bsh plate back on and unplug the rear pcv and vent to atmosphere and see what happens. as for the intercooler pipe i think i may put a piece of a bike tube around the coupler behind the oring and see if that tightens everything up, heres hoping the tube doesnt melt!


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## kylegti07 (Apr 4, 2012)

dirka you may also want to try putting your stock diverter valve on, if it is the newest revision it may help the situation, many guys have said that apr software doesnt like aftermarket dv's, just a thought!


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## ohDirka (Jul 13, 2012)

kylegti07 said:


> dirka you may also want to try putting your stock diverter valve on, if it is the newest revision it may help the situation, many guys have said that apr software doesnt like aftermarket dv's, just a thought!


Yeah I had the Rev D on it before. I dont think that the DV is the cause. Also I have not read anything bad about the AWE DV. 

I'm just going to check the seal around the PCV block off and make sure it does not have any leaks. If there were a leak of the positive crank pressure under full load it would cause the misfire/fuel cut feeling.


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## warranty225cpe (Dec 3, 2008)

Honestly, you really need to know what your plugs are gapped to. They will misfire if the gap is too big. I would start there. If your gaps are fine, I would be checking harness and connectors for shrts to ground and corrosion.


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## everfresh59 (Jul 26, 2010)

Just an update on my ongoing performance issues resulting in misfires on Cylinder 3. In the last 2 weeks, I changed the following items:



Coils
Plugs (NGK Iridium's)
Fuel Filter
Cleaned MAF Sensor
Cleaned Air filter (Carbonio)
TB Alignment (APR)
Check DV, no problems

There was pretty much no change whatsoever; cold start is still rough, along with idle. Boost seems to be on and off, and when it doesn't work, I get temporary blinking CEL. It seems to happen randomly regardless of where I am in the rpm or gear. I've come to the conclusion that it occurs when the engine is at running temp, but I obviously won't go woot if the oil hasn't gotten up to normal temps to verify this assumption.

After all the Googling, I've come to realize that it is most likely a bad fuel injector in #3. Since I've just gone past the 100,000 mile marker, I've now decided to opt to the inevitable:



Remove manifold and clean out intake valves with some Chem-tool and elbow grease.

I just purchased some used Fuel Injectors off of a 2008 GTI which only had 30,000 miles. Only cost me $130.00 shipped for all four. 

Instead of just throwing them in, I'm going to have them Ultrasonically cleaned to ensure they are in top shape.

New Injector O-Ring/Clamp Kits, Intake Manifold Gasket and Throttle Body Gasket.

Debating on wether to replace Intake Manifold as well.

Thermostat since I'm already there.

S3 intercooler if I can find one for sale.


On top of all this, I have to replace my front swaybar bushings, which of course is going to make me want to upgrade for s**ts and giggles, and prolly do the rear as well. 

FML.... but I wanna go woot again!

This is what she looks like at the moment!


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## warranty225cpe (Dec 3, 2008)

everfresh59 said:


> Just an update on my ongoing performance issues resulting in misfires on Cylinder 3. In the last 2 weeks, I changed the following items:
> 
> 
> 
> ...


 What is your plug gap? I would call the guy that did your work and ask. The. Pull them and check.


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## everfresh59 (Jul 26, 2010)

warranty225cpe said:


> What is your plug gap? I would call the guy that did your work and ask. The. Pull them and check.


I had the gaps checked from the same shop. Everything was spec. I've reset the codes enough times and my only conclusion is either bad injector or cam follower. I'm gonna check the follower, but I had all that replaced under warranty last year and have since been checking it every 6 months. 

I'm almost certain it's the injector since it's only #3 that's giving me the issues.


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## kylegti07 (Apr 4, 2012)

hey everfresh have you gapped the plugs to .028? i know it seems like a smal difference but it does help and the tool is 1.50 at autozone. also have you check your n75 or n85 valve"i cant remember which" apparently a lot of guys have boost issues, misfires, cold start and idle issues because of this valve, its only 85 bucks on ecs id start there......


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## warranty225cpe (Dec 3, 2008)

kylegti07 said:


> * hey everfresh have you gapped the plugs to .028? i know it seems like a smal difference but it does help and the tool is 1.50 at autozone. *also have you check your n75 or n85 valve"i cant remember which" apparently a lot of guys have boost issues, misfires, cold start and idle issues because of this valve, its only 85 bucks on ecs id start there......


That's what I'm trying to say. If it's the injector, that's great. But what's missing, are the basic steps to trouble shooting. You have to know where your starting out. The basics will always lead you to your conclusion. Keep it as simple as possible. It's easy to overthink things and waste your time chasing your tail. Forum advice can make that worse.


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## everfresh59 (Jul 26, 2010)

warranty225cpe said:


> That's what I'm trying to say. If it's the injector, that's great. But what's missing, are the basic steps to trouble shooting. You have to know where your starting out. The basics will always lead you to your conclusion. Keep it as simple as possible. It's easy to overthink things and waste your time chasing your tail. Forum advice can make that worse.


Yea, shop checked the gap for me even though he insisted they would be fine. I have a n75 somewhere, which is what I'll probably do as well. I replaced my pcv and breather hose last year, but haven't checked it.

I still have a week anyway before I can bring the car to the shop, so I'm gonna do these thing and see what happens. I still haven't ruled out fuel rail either.


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## warranty225cpe (Dec 3, 2008)

everfresh59 said:


> Yea, shop checked the gap for me even though he insisted they would be fine. I have a n75 somewhere, which is what I'll probably do as well. I replaced my pcv and breather hose last year, but haven't checked it.
> 
> I still have a week anyway before I can bring the car to the shop, so I'm gonna do these thing and see what happens. I still haven't ruled out fuel rail either.


You can't trust a shop to tell you things. You need an actual number. WHAT IS YOUR PLUG GAP? You need to know this. Your doing things backwards. Start with the basics.


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## ohDirka (Jul 13, 2012)

warranty225cpe said:


> Honestly, you really need to know what your plugs are gapped to. They will misfire if the gap is too big. I would start there. If your gaps are fine, I would be checking harness and connectors for shrts to ground and corrosion.


I checked the gaps before I put them in approx. 10k mi. ago and they were all .28. I dont think that going stage 2 that I would need to drop the gap or go to a stage colder yet. I would also think that if it were plug gap that I would experience the misfire more often than only in 4th when I hold an rpm then go WOT, correct? 

I'll check the plug gap tonight when I take off the cover to check the PCV for leaks.


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## warranty225cpe (Dec 3, 2008)

ohDirka said:


> I checked the gaps before I put them in approx. 10k mi. ago and they were all .28. I dont think that going stage 2 that I would need to drop the gap or go to a stage colder yet. I would also think that if it were plug gap that I would experience the misfire more often than only in 4th when I hold an rpm then go WOT, correct?
> 
> I'll check the plug gap tonight when I take off the cover to check the PCV for leaks.


 If your plug gap is too big, you will experience spark blowing out at* higher* RPMs. Thats why I suggested you check them. If you pull them and they are .28, drop them down to .25-.26 and see if the misfires are any better. If not, thats fine. But that really is where you want to start. easy to check the simple stuff first. If the misfires get better, drop a heat range colder and play with the gap a little.


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## everfresh59 (Jul 26, 2010)

warranty225cpe said:


> You can't trust a shop to tell you things. You need an actual number. WHAT IS YOUR PLUG GAP? You need to know this. Your doing things backwards. Start with the basics.


He did it right in front of me...lol. Your saying I shouldn't trust him or the tool he used?


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## warranty225cpe (Dec 3, 2008)

everfresh59 said:


> He did it right in front of me...lol. Your saying I shouldn't trust him or the tool he used?


Im saying check it.


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## ohDirka (Jul 13, 2012)

warranty225cpe said:


> If your plug gap is too big, you will experience spark blowing out at* higher* RPMs. Thats why I suggested you check them. If you pull them and they are .28, drop them down to .25-.26 and see if the misfires are any better. If not, thats fine. But that really is where you want to start. easy to check the simple stuff first. If the misfires get better, drop a heat range colder and play with the gap a little.


Okay, Thanks for your input. I was thinking I may as well check the gap anyways because its something that is so simple and fast to do. :thumbup:


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## ina04gli1.8t (Sep 24, 2010)

Update, had all four injectors replaced under warranty, no carbon buildup says the tech, installed bsh catch can and two weeks later same issue. If it's not a hardware issue then what ?


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## warranty225cpe (Dec 3, 2008)

ohDirka said:


> Okay, Thanks for your input. I was thinking I may as well check the gap anyways because its something that is so simple and fast to do. :thumbup:


Gotta start with the basics or you'll drive yourself nuts



ina04gli1.8t said:


> Update, had all four injectors replaced under warranty, no carbon buildup says the tech, installed bsh catch can and two weeks later same issue. If it's not a hardware issue then what ?


Still getting the injector code?

(Sorry, there are more than one person asking questions about their specific issue. It can get a little confusing)


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## arismkv (Jun 17, 2008)

I know my brother had this issue with his passat 2.0t automatic fsi. Valve cover gasket was leaking some oil into the spark plugs. 

So fixed that. Also made sure to get oem Bosch plugs. I believe they work best with apr tune. Also changed coil packs. No more misfires.


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## judderz123 (Sep 27, 2013)

*Help me Plz !!!!*

Hi every1 I've just read this thread and signed up because I'm having the exact same problems as u guy and I'm am still no closer to solving my problem after spending 2.5k and sending it to many garages including some of the best with no look i have a seat leon 2.0 tfsi fr mods as follows been running with these mods for 2 years before this problem started.
Revo stage 3 remap
Full mill trek 
Rs4 injectors
ITG induction kit
Brand new loba hpfp
4 brand new red coil packs
4brand new ngk laser platnums
K04 turbo 
Sps switch
Sachs clutch
Now recently I was driving up hill at full throttle wen I heard a pop and the car started to misfire realy badly so I pulled over and got a friend to come who also owns a tfsi (s3) my good friend swapped his coil packs over and the car was fine no misfire the car drove fine so we drove to the garage in my car and bought 4 brand new red coil packs fitted them and the car was fine however the next day the boost started to get iratic and cut to stock boost not limp mode just stock boost 10 psi u will drive along and have full boost 1 minute and then stock boost the next then it got to a point till it's stuck in that mode till u reset it via computer or take it on a motorway run and build the revs up threw the gears and it will give u boost the misfire seems to be at idle u can hear the pop pop pop. Pop. Pop pop and u can watch the computer count the misfires from cylinder 3 from left to right roof facing the engine so we swapped injector 3 with injector 4 and the misfire followed so we got brand new injector this morning and put it in and I still have the misfire in cylinder 4 the stupid thing is the car can be reset and it will run fine for a while full power and then when u let it idle it starts to misfire and cut boost I don't no wer to turn with this now after spending all this money on new bits and labour all the checks done compression smoke test leak test ect someone Plz help !!! Any help would be apeciated


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## warranty225cpe (Dec 3, 2008)

judderz123 said:


> Hi every1 I've just read this thread and signed up because I'm having the exact same problems as u guy and I'm am still no closer to solving my problem after spending 2.5k and sending it to many garages including some of the best with no look i have a seat leon 2.0 tfsi fr mods as follows been running with these mods for 2 years before this problem started.
> Revo stage 3 remap
> Full mill trek
> Rs4 injectors
> ...


That popping sound sounds more like a big boost leak than ignition related.


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## everfresh59 (Jul 26, 2010)

Just a quick update and finally a resolution to all my woes... My MAF was on it's last leg, and after driving to work today without the MAF connected, I had zero issues hitting boost in 5th/6th gear at low rpm. She ran perfect all the way to work, without any blinking CEL.

What I was wondering though... I cleared my codes last night, and then tried to clean my MAF one more time. When I started her up this morning, blinking CEL was there after 4-5 seconds. I turned off car and unplugged MAF. When I started her again, it was clearly evident the MAF was my problem since the idle was back to the way it should be. My question: Is it normal to not have a CEL with the MAF completely disconnected... because I had no CEL whatsoever on the drive to work.


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## ohDirka (Jul 13, 2012)

everfresh59 said:


> Just a quick update and finally a resolution to all my woes... My MAF was on it's last leg, and after driving to work today without the MAF connected, I had zero issues hitting boost in 5th/6th gear at low rpm. She ran perfect all the way to work, without any blinking CEL.
> 
> What I was wondering though... I cleared my codes last night, and then tried to clean my MAF one more time. When I started her up this morning, blinking CEL was there after 4-5 seconds. I turned off car and unplugged MAF. When I started her again, it was clearly evident the MAF was my problem since the idle was back to the way it should be. My question: Is it normal to not have a CEL with the MAF completely disconnected... because I had no CEL whatsoever on the drive to work.


I have a spare MAF laying around I'll throw it in and see if the problem persist.


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## everfresh59 (Jul 26, 2010)

ohDirka said:


> I have a spare MAF laying around I'll throw it in and see if the problem persist.


Did you test the MAF? 

My car has been acting really weird, I've had this cyl#3 misfire for a while now and I'm still on my original MAF. Yesterday night, I scanned my car and decided to check group032 in VCDS to see if the culprit could be my o2 sensor, scan came back normal, so I ruled it out. I cleared all my codes before doing this, and now I have zero boost issues in any rpm range/gear. What's really weird, is that I get a blinking CEL on a cold start. It only lasts for 10-15 seconds and then disappears, CEL is completely gone. 

The temperature has dipped this weekend, so I'm not sure if this could be the reason, but I'm now completely out of ideas. I'm picking up a used MAF today to see if that works, but other than this, the only other thing I can think of that could be an underlying issue is a vacuum leak or dead thermostat? I'm no expert, but open to any great minds in helping me out.


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## ohDirka (Jul 13, 2012)

everfresh59 said:


> Did you test the MAF?


No. I was going to last weekend, but the temps dropped here as well and it wasnt doing it when I tried to do a log. Yesterday when I was getting on the highway it misfired in 4th again though and I havent had time to hook up vag-com to see what it was. I'll throw in the spare MAF this weekend hopefully. I did clean my MAF a few months ago (before stage 2) but who knows maybe its just going out. I'll report back when I do the test. :thumbup:


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## ohDirka (Jul 13, 2012)

cleaned the MAF and check spark plug gaps. Still having misfires under full boost. Going to buy another coil pack and swap them around to see if I have one that is defective.


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## karlton770 (Apr 9, 2013)

I'm having the same exact problem. Only in 4th gear. Did you ever find the solution?


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## xiaohong (Oct 11, 2013)

everfresh59 said:


> Just an update on my ongoing performance issues resulting in misfires on Cylinder 3. In the last 2 weeks, I changed the following items:
> 
> 
> Coils
> ...



Just to share my experience on misfiring:

1) All coil packs changed
2) All new plugs - BKR8EIX - Gapped to 0.65
3) New OEM injectors - Old injectors were covered with carbon buildups and crapped
4) Full engine clean and de-carbonize - stripped the entire engine and cleaned everything out - especially the intake valves
5) New piston rings
6) New gaskets
7) New hoses for supercharger & hoses for intercooler (CTS Turbo)
8) New turbo gaskets
9) New DP gaskets
10) New Belts
11) New Engine oil - Using Motul 300v
12) New coolant G13 
13) New DSG oil
14) On Eurosports Performance Tunning - Custom Stage 3+ map with WMI at 70%
15) New fuel filter
16) New Coil Pack Connectors
17) New Breather Valve
18) New DV Rev. D
19) New Hybrid Turbo (Just in case, mate has got my old hybrid)

On a side note, the fuel injectors rarely spoils and if they do, replacing should do the trick but that didnt work out for me. Damm costly injectors 

However, upon starting the car, it was fine for like 5 mins until the misfiring came back on idle. WOT on 4th gear to 6.2rpm will indicate CEL flashing and signs of misfiring.
Random multiple misfire and if I push it harder, it will register an EPC and then cylinder will shut down. *sounds like a boxer at that moment*

Few things that I have noticed, even when flashed back to stock map, it is still misfiring but not as bad but the same symptom remains. 

It has been 6 months now and I am still trying to figure out what is wrong.

Normal drives, it will not misfire and smooth as a brand new car, depends on the car's mood, at times under WOT it performs beautifully and no issues if I keep the rpm at 5.8k limit and manually shift the gears.

The MAF sensor has been cleaned and also replaced still no avail ans on misfiring on all cylinders

The last resort I have in mind is to replace the entire wiring from the CAN Gateway till the engine bay area as I suspect that the wires are old and with heat buildup, probably the circuit is not 100% and snaps at a few places but not totally dead yet. Even with a multi-meter, the wires seems ok but with hand feel, it seems hard and tough which wiring should be slightly more flexible.

Welcome to the misfiring club guys........

Hopefully I can solve it and share my experiences with all and solve it together too......

-1 Misfiring....... :facepalm:


Then I decided to do an entire clearing of DTCs and also reset learning values:


Thursday,30,January,2014,21:47:51:23029
VCDS -- Windows Based VAG/VAS Emulator
VCDS Version: 12.12.0.0
Data version: 20130910


VIN: XXXxxxXXXxxxXXX License Plate: xXxXxXxX
Mileage: xxK Repair Order: xh0001



--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


Gateway Installation List: xXx xXx xXx XX

01-Engine -- Status: OK 0000
02-Auto Trans -- Status: OK 0000
03-ABS Brakes -- Status: OK 0000
04-Steering Angle -- Status: OK 0000
08-Auto HVAC -- Status: OK 0000
09-Cent. Elect. -- Status: OK 0000
15-Airbags -- Status: OK 0000
16-Steering wheel -- Status: OK 0000
17-Instruments -- Status: OK 0000
19-CAN Gateway -- Status: OK 0000
25-Immobilizer -- Status: OK 0000
42-Door Elect, Driver -- Status: OK 0000
44-Steering Assist -- Status: OK 0000
46-Central Conv. -- Status: OK 0000
52-Door Elect, Pass. -- Status: OK 0000
56-Radio -- Status: OK 0000
75-Telematics -- Status: OK 0000
77-Telephone -- Status: OK 0000


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## ohDirka (Jul 13, 2012)

I still have not found a solution. As of right now in getting close to 75k miles so I am treading carefully until I get my timing belt and water pump replaced. After I do that I think I might do an intake clean to see if that solves the problem, but I'm going to wait until winter is over to do that.


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## xiaohong (Oct 11, 2013)

Solved


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## ohDirka (Jul 13, 2012)

xiaohong said:


> Solved


Care to share what you did to fix it?


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## xiaohong (Oct 11, 2013)

Reduce timing slightly


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## ohDirka (Jul 13, 2012)

xiaohong said:


> Reduce timing slightly


Explain how you did this on the stock ecu with a tune... That is an engine parameter that can not be changed with Vag-com.


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## xiaohong (Oct 11, 2013)

ohDirka said:


> Explain how you did this on the stock ecu with a tune... That is an engine parameter that can not be changed with Vag-com.


Not stock tune... its on a stage 3+ map equivalent. 

The valve lifters and seats were causing issues. Changed valve lifters and reseat the valve lap areas and its perfect. One arm and half a leg tho


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## sethlivingston (Sep 27, 2014)

I had a massive leak in my valve cover gasket that leaked oil into the spark plug wells. I replaced the gasket and installed new plugs, but I'm getting a misfire on cylinder #4. I'm thinking it's reasonable to replace the coil despite some of the posts on this thread, since it was soaked in oil at one point.

Dumb question: if I'm looking at the engine after opening the hood, cylinder #4 is on the far right... right?


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## sethlivingston (Sep 27, 2014)

sethlivingston said:


> I had a massive leak in my valve cover gasket that leaked oil into the spark plug wells. I replaced the gasket and installed new plugs, but I'm getting a misfire on cylinder #4. I'm thinking it's reasonable to replace the coil despite some of the posts on this thread, since it was soaked in oil at one point.
> 
> Dumb question: if I'm looking at the engine after opening the hood, cylinder #4 is on the far right... right?


I replaced the ignition coil in the #4 cylinder, which is the one on the right, and everything is running smooth again. :thumbup:


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## mlody91 (Mar 12, 2014)

Reviving old thread. 

Had a manual valve cleaning service done about 10k miles ago and had all my stock coils and plugs replaced with R8 red tops and NGK plugs. Had no issues whatsoever up until 2 months ago where my car would randomly misfire in all four cylinders (p0300, 0301, 0302, 0303, 0304) on cold starts and cold starts only. Have yet to replace the coils and plugs because again they were replaced 10k miles ago and I don't believe that they are the root cause of the issue. 

Has anyone gotten to the bottom of all this? I know someone mentioned valve lifters and valve gaskets. Did this remedy the issue? If so, is it DIY-able? 

Cheers, 
Mlody91


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## HereticByDefault (Mar 19, 2009)

Just started having this problem last week. Here are my troubleshooting steps as of now:

Replacing the ignition coil connectors

Checking the plug gap on the BKR7EIX plugs

Ordering some laser platinums in the meantime since they're cheap and they worked fine.

Considering doing the valve cover gasket cause I do have a good amount of oil leaking into the spark plug wells.

Not sure where else I could go from there so I'm hoping somewhere along these steps it'll go away. I'll post an update when this is done

Sent from my SM-G900T using Tapatalk


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## MyFastIsRed (Apr 23, 2009)

Im having a very similar issue, I just read through this whole thread and couldn't find the answer I am looking for

I have misfires in cylinder 2 and cylinder 2 only, I ran a log and its misfiring like crazy

I replaced the sparks and made sure they were properly gapped for a stock 20.t tsi at .032 and I swapped the coil packs

re ran the log and still misfiring in cylinder 2 only

at idle the rpms are fine and hover around 8-8.5 with no fluctuation but the motor shakes the whole car

CEL is on throwing a misfire code p0302 so just misfire in cylinder 2.. at WOT the cel will flash sometimes 

if its just cylinder 2 its got to be an injector right?


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## Pottle (May 5, 2006)

After reading this entire thread, its weird that nobody has a solid fix.


After replacing my plugs and coils, still getting random misfiring. Sometimes my CEL will go out, others it will flash than go solid. Reading about carbon build up and not sure to tackle the valve cleaning or injectors first. Just want my damn CEL to go out so I can get my car inspected.


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## HereticByDefault (Mar 19, 2009)

I'm pretty sure my specific problem is the ignition coil connector as I'm getting P1361 (cyl 3) and related code for cylinders 1 and 2: Ignition Circuit: Open Circuit. I accidentally got the 8K0 connectors instead of the 4B0, so when the right ones come in I will be replacing them and posting back.

@MyFastIsRed: Did you try swapping the cyl 2 coil pack with a different cylinder to see if the misfire follows? 

Sent from my Nexus 7 using Tapatalk


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## Barn01 (Feb 26, 2011)

MyFastIsRed said:


> Im having a very similar issue, I just read through this whole thread and couldn't find the answer I am looking for
> 
> I have misfires in cylinder 2 and cylinder 2 only, I ran a log and its misfiring like crazy
> 
> ...





Pottle said:


> After reading this entire thread, its weird that nobody has a solid fix.
> 
> 
> After replacing my plugs and coils, still getting random misfiring. Sometimes my CEL will go out, others it will flash than go solid. Reading about carbon build up and not sure to tackle the valve cleaning or injectors first. Just want my damn CEL to go out so I can get my car inspected.


I had the P0302 as well (Misfire on Cyl #2) I had it a few times last winter and just cleared the code 4-5 times. It was fine most of the spring and summer but in the past month it was occurring every morning. I had swapped coils and plugs as well as regapped and no change. I had a strong feeling it was carbon buildup. So on the weekend I took on the crappy task of pulling the intake and cleaning the valves. All I can say is WOW! There was so much carbon built up in the valve housing that I couldn't tell what valves were open or closed and could barely see the valves. For the record I have 250K Km's on the car and this is the first cleaning. So once I scrapped and wire brushed everything and put it back together there were a bunch of codes that I had to clear initially and now no more P0302 #2 misfire. I can tell you first hand that there is no intake spray in the world that is going to remove that carbon build up. Seafoam won't do squat against this stuff! I had to chisel it off with a screw driver, suck it out and then wire brush on a drill while filling it with de-greaser then clean the whole thing out with brake cleaner.

Overall it was worth it and I hope that's the last and only time I have to do that job. The car does feel a bit smoother and seems to idle a bit better. Nothing dramatic but there is an improvement.










Note if you are going to attempt this there are a few special tools you MUST have!

- A jack to get the drivers side of the car up. You have to take off the lower intake turbo hose because you'll need to disconnect from the butterfly valve off the intake
- #30 Torx bit
- Inspection mirror makes removing and putting the bolts into the blind spots on the butter fly valve that much easier.
- 4mm socket to remove the oil dipstick stud (You have to twist the dipstick out of the way and then wiggle and pull it out to get access to the lower support bolt, don't worry it separates just below the bolt).
- M10 Triple square *Stubby* (not short) socket. If you don't have this you will never get out the lower support bolt (satan bolt) behind the butterfly valve.
- Universal joint for the socket above
- Extendable magnet (mine has an LED on the end and I recommend this), for pulling the bolts out of the intake guide and for taking out the satan bolt.
- 13mm socket for upper support nut
- 10mm 1/4 drive socket and 6" 1/4 drive extention for both lower ends of the intake manifold
- Small flat long neck screw driver for chiseling out the carbon
- Shop vac for sucking the crap out of the valve housing
- Inline wire brush like a shot gun bore brush (put the shaft in a drill)
- Can of heavy duty degreaser or carb cleaner
- Can of brake cleaner

Oh and if you've never changed your cam follower then I suggest you get one from the dealer. I took my HPFP off with the intake assy so it's 10sec to change the cam follower.

If anyone is going to do this and wants help feel free to PM me while it's still fresh in my memory.
I have yet to find a video for this specific engine (2.0T FSI BPY). All the ones I've seen are for the newer TFSI with the oil filter on top. This disassembly has issues that you won't find in those videos.


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## One Eyed Jack (Jun 5, 2007)

*Misfire???*

So, perhaps this is related. About two months ago I had the HPFP failure (@ about 110000 mi.). The local dealership diagnosed shavings in the cam bearings and that bought me a brand new and complete top end.  About 1 month ago I started getting a very random misfire (bucking, power loss at speed, stalling if at idle). It seems independent of engine speed, engine temp., or load. NO CEL or OBDII codes are thrown. When it isn't bucking, it runs great, and my mileage is as good as ever. I thought about water in the gas. Ran a few tank fulls with drygas. No help. Thought about a clogged injector. Ran a few tank fulls with Techron. No help. Thought about a dirty MAF (it has a K&N CAI). Cleaned the MAF with commercial MAF spray cleaner. No help. Before I give it back to the dealer ("We're unable to reproduce..."), are there any other suggestions? Thanks in advance.


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## HereticByDefault (Mar 19, 2009)

Forgot to post back here when my issue was resolved. It was an ECM ground wire behind the driver side headlight that was not grounded properly.

Sent from my SM-G900T using Tapatalk


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## floydhe (Feb 7, 2018)

*Warranty's Comments on basics*

This guy right here, Warranty229, listen to him. 

He was right....stick to the basics.... I had the same problems as you all discuss...

I changed PCV, rear main, turbo wastegate, all after replacing all four plug/coils on a 2.0 Audi turbo...

All in all, it was the plugs that I installed in the beginning - not gapped properly (i thought they were pre-gapped from parts house)

As it turns out, I fixed the problem with the pcv and rear main seal, but created a new similar one with the plug gaps not being right. It took 3 days and this forum to get me back on the plugs....

And just like user Warranty said, I was chasing my tail overthinking the basics......


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## Irishbri (Oct 29, 2014)

Holy thread revival Batman.....

Anyway......is it possible that a major exhaust leak could cause misfires due to reduced compression? Because I had carbon cleaning done about 1.5 years ago and I just changed coils and plugs.....


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## ROH ECHT (Dec 9, 2010)

Doubtful but depends on how the O2 is reading and reporting to the ECU. 

Most MISFIRES are a simple fix but can be a multitude of possibilities:
Proper plugs gapped and installed properly
a failing coil
a failing MAF
carbon build-up on intake valves
Bad PCV
rarely an injector
*a worn cam lobe* due to failed/seized roller rocker arm or condensation pitting is becoming a bit more common
timing belt installed incorrectly or "skipped"
cam chain tensioner worn or malfunctioning; but to be replaced along with a new chain
could just be a clogged screen inside the cam chain tensioner cover
and more....


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## Irishbri (Oct 29, 2014)

Thanks man....


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## ROH ECHT (Dec 9, 2010)

What cylinders are misfiring? All or is it cylinder specific? DTC Codes are?


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## Irishbri (Oct 29, 2014)

Its 2 qnd 3..... 

The reason I was thinking sub systems is that the car actually runs fairly well....My fuel mileage is normal and really I am mostly just getting a rough cold start idle.....

I did a resonator delete and the pipe they welded in is shot....I just havent gotten around to having it replaced.....

I would think that the symptoms would be worse (or at least worsening) if it were carbon build up or a vacuum leak.....


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## ROH ECHT (Dec 9, 2010)

I just added a Bad PCV to the above list because I just saw I left it out.
Here's my channel and in it I show how you test the PCV...if you still run the oem PCV; https://www.youtube.com/user/zoomdis/videos


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