# 2005 Jetta 5 cylinder 2.5 motor diagnosis and swap DIY



## bugwrencher (Nov 8, 2010)

​First of all, this is my first post, and I have just become a member to vwvortex simply to make this post. Also this is my first blog ever, so if the format isnt right, or pictures or video do not work, dont spend space complaining, just let me know how to make this thread better.
Now down to business.
I have decided to make this thread because I am working on a 2005 jetta 2.5 and have searched and searched for some good information on this engine because it is fairly new to me. Now while I have found some good info on this and other blog sites, there seems to be alot of confusion about what is destroying these motors, how to fix it, should you attempt to fix it, when does it happen, how much is VW going to charge you if you take it to them, etc.
So I am going to use my own personal experience to help others, and maybe someone will be able to help me or make a suggestion if I get into a snag. Also, I do not work for VW, I do not work at a foreign car shop, I do not even own a bentley manual for MK5, the only resources I have been using for this job is the info I have found on the internet, Mitchell on Demand from the napaprolink website, and 50 combined years of experience in motor rebuilding and machine work between me and my boss who has been helping me strictly on an informational basis, so if I seem to be doing things differently than the book says, that is because I am mainly working with instinct, also, if someone notices something in the book that might help me, please let me know. 
While we rebuild many VWs (mostly type1, mk1, 2,3, and every now and then 1.8t) at the machine shop, we have never even done a head for the 2.5 gas motor. So while I may be new to this engine, I am not new to VWs, I have been working on them and owning them all of my life (10 cars and counting years 1963-2002, and everything in between, I also am a early diesel guru), and have never needed to take one to a shop for anything but an inspection. Also this job is being done in my back yard, with no lift, and as non-technical as possible to prove that anyone with a good full set of torx can perform this job and save thousands on labor charges. I plan on placing the whole job on this thread with good detailed pictures. The job is mostly done already, IE the thread is about 2 weeks behind me, so if you have a question about a later step that may not be on here yet feel free to ask. So enough with the introductions, my next post will be explaining the customer complain and what got me involved in this mess to begin with.


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## bugwrencher (Nov 8, 2010)

*Customer Complaint*

The car actually belongs to my future sister in law, she bought it used with around 40000 miles on it from a local VW dealership. The car right now has around 100000 on it, I forget the actual mileage but ill take a pic before I start the new(used) motor. Some background on owner: She maintained vehicle regularly as far as oil antifreeze and other basic maintenance. She does drive it rough, she lived in the city and drove it like people in the city do, floor it in between red lights and stomp the brakes when the light turns red. 

Though she did drive it rough, it should not have been enough to break the motor, especially with the regular oil changes. She brought it to me because it was hard to start, vibrated roughly at idle and had the engine light on. When I read the code with vagcom(i forget what number it was) it was something about the cam sensor being out of whack or something like that. I looked the engine all over for bad connections, vacuum leaks, dirty throttle body etc. and seen no problems, looking back on it now I really wish I would have pulled the valve cover because I would have been able to save the motor. But she was in a hurry and traveling so I did not pull the valve cover or timing cover to see what had happened. So I told her that it was nothing that I could find right then. 

So I got in the car to drive it to the other side of the driveway for her and when I hit the key, I heard the valves hit the pistons. After that I did pull the valve cover and timing cover, and found nothing that seemed broken or disconnected in the timing cover, however I did see that all the intake valves were bent. So no problem, I work at a machine shop, I can fix that. Wrong. At the time of this post there are very few aftermarket parts are available for the 2.5. in fact the only aftermarket part I can find as of now is the head gasket and the timing chain itself. I could not find a head gasket set, timing chain tensioner, guides, or valves. Also a camshaft locker would have to be purchased or fabricated because the sprockets are keyless. These parts would have had to come from the dealership.

I do not know the price of what VW gets for these parts because I never even called them, so for some people fixing their motor with VW parts maybe the best option. Not for me. I called around and found a good used motor with 60000 on it for 600 bucks locally with free delivery and a limited lifetime warranty. Sidenote: this was not the motor I would have preferred because by my count this motor may only have 40000 good miles left on it. There was another motor locally that I recommended that was only 1200 dollars and had only 1000 miles on it from a crash test dummy. But money is tight, and this job is being done on budget, then she will sell the car when I am done. So the motor was delivered to my shop in one piece so I started disassembly of the car, which I will cover, with pictures(hopefully), in my next post.


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## bugwrencher (Nov 8, 2010)

*Tear down*

Pulling the motor out is relatively simple. It is almost like VW made this motor to fall right out of the car so they could make easy repairs. Because I am in my backyard with no lift I decided to bring the motor out the front, however Mitchell says to take it out the bottom. First is removing the battery for safety. I feel the need to mention about the air box/motor cover because of some questions on other blogs, simply unhook the big hoses and the cover lifts strait off. The battery box can be removed then, then bumper cover, headlights, bumper, and plastic off the front. Tip: the hood latch actually has a connector around the front of the drivers fender so unhook that connector and the front end can be completely removed from the car.

Also, I attempted to do this without loosing the freon from the condenser and there was not enough give in the hose to get the clearance I wanted so I ended up removing the ac lines, and condenser and radiator from the front plastic piece, just to make the job cleaner and an easier shot when pulling the motor. Then the wiring harness can be removed. Take your time and use the right tools to not break any connectors, if you break the end off of any connector it is really hard to remove the connector without breaking it to pieces. I broke two connectors that luckily were included with my new(used) motor, which I will later solder and shrink wrap. 

Other notes on removal are the axles are actually not bolted to the transmission. the clamps have to be removed from the boot, then the boots pulled back and the axle will just pull right out of the transmission. That is after you already press or beat them out of the hub, into which they are press fit, or mine were anyway. Get the exhaust and rear motor mount off while you are under there. The motor will just be hanging from the driver and passenger mounts now. 

And while I cannot remember every detail, mostly its just the shift control which just pops off, the heater core lines, which I just popped the clip on the plastic and quick disconnected them, and the fuel and water lines on the passenger side of the motor, as well as the water reservoir. Then hooked it to the cherry picker, undid the motor mounts and pulled the thing on out. This job is pretty strait forward and anyone who has experience pulling the motor on any VW after 75 will not have a problem and probably already has any special torx to do the job. 

























Sorry there are a few details missing in the photos, but I was ripping at this point and did not take many pics. I will try to slow down and take more pics from now on.


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## thygreyt (Jun 7, 2009)

wow.

nice thread!


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## nothing-leaves-stock (Mar 1, 2005)

nice, but a question...what are you talking about the axles aren't bolted in?? they are.


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## bugwrencher (Nov 8, 2010)

*Reply*

Sorry for being unclear. The axles on this car are bolted to the hub, however they are not bolted to the transmission. To remove from the trans the boot must be removed and then the axle just slides out. Also I did not mention earlier but this car is automatic so some details may be different if yours is a stick.


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## dogsanddubs (Jul 6, 2008)

Subscribed.

Thanks for taking the time to post this and what is coming up


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## 08Rabbit1 (Jun 30, 2008)

You missed a step - what's wrong with the car, and what's the evidence that "something is destroying these motors", especially given that your shop hasn't ever even done a head on one? My parts guy has one with 150k and no sign of a problem.


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## dogsanddubs (Jul 6, 2008)

bugwrencher said:


> ... I heard the valves hit the pistons. After that I did pull the valve cover and timing cover, and found nothing that seemed broken or disconnected in the timing cover, however I did see that all the intake valves were bent...





08Rabbit1 said:


> ...what's wrong with the car....


Problem with the car: Bent valves, the timing is off, and pistons would need to be inspected


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## 08Rabbit1 (Jun 30, 2008)

I was asking more about the source problem, but I guess you're saying you don't know, yet. If the chain is in place and the timing off / valves bent doesn't it have to be the cam gear?


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## bugwrencher (Nov 8, 2010)

Hey everybody sorry for not posting in the past couple of days, but my work got backed up. I do plan on posting the next part of my job either tonight or this weekend some time... I also plan on putting the motor back in the car this weekend, so if I dont post untill monday that is the reason. This next post will cover splitting the motor and trans as well as trying to diaganose the problem. Also, from what Ive been reading on this and other sites the timing chain problem does not happen to all of these motors, especially if they are not driven hard... some people love these engines and puts lots of money in mods and stuff... but it is happening to some of them, especially as more miles get on them. And from what my customer says, who is defenetly not a mechanical person, the engine did not sound any different to her and gave no signs of failure when it initally skipped timing.


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## aufmitterspeil (Jun 24, 2008)

These MY05 2.5's had few more issues than the proceeding years, no?


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## bugwrencher (Nov 8, 2010)

While I am not exactly sure if later years are going to have this problem or not, this is a 2005, and alot of the other complaints Ive read are from 2005 cars... so VW might have seen this as a problem and changed the design or something. Again I do not know for sure about other years, just my experience with this car and what Ive been able to find on the internet.


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## PanzerVW (Jan 9, 2003)

subscribed..interested in seeing where this thread goes..may be helpful diy for future reference


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## bugwrencher (Nov 8, 2010)

*diagnosis (finally)*

Alright, the next thing that I did was split the engine from the trans. This is pretty straight forward so Ill be brief. Like I wrote before, this car is an automatic. So first is unbolting the torque converter so it does not fall out of the trans. To do this, remove the plug located on the back of the engine block right by where the passenger side axle slides in. Then just remove the 6 nuts that appear in the hole when you turn the engine over. NOTE, if you are planning on reusing the engine make sure you turn it over clockwise. If you turn it counter clockwise it will skip more teeth on the chain and could damage the engine… even if there is nothing wrong with the engine when you pull it out, turning counter clockwise could cause it to skip time. After all the torque converter nuts are off, just remove the starter, trans cooler lines and mounting bolts and slide the trans out, being very careful to not let the torque converter fall out of the trans. 










































The next thing I did was remove the timing cover and valve cover again (I had put them back on before removing the engine just because I did not know I was going to be doing this job at that point), so like I said earlier there was nothing really obvious on first inspection. So I pulled the cover off the engine that was purchased to go back in this car and seen that the chain is far tighter on the new engine than the one that came out. Sorry I do not have pics, but the new(used) engine is at my work, and I did not have my camera when I pulled the cover, and I put it back on the same day. But I do have pics of the engine that came out and can explain what the new engine looked like. 

















This is the lower gear that hooks the top end to the bottom end. On one site I saw a guy that had one of these engines where this gear is completely rung off... no teeth left. This gear appears to be worn a little but not enough to skip. It is sharper than the other gears though. 









Yes I know that the upper guide is gone, I removed it while trying to remove the chain and cams without removing the gears. this, however, is not possible, so dont try. This guide is not very thick and barely changes how far the plunger comes out of the tensioner. 

Okay I know it is hard to compare these pictures to an engine that I have no pics for… but on this engine the tensioner is coming out of the housing at least twice as far as the new (used) one. On the new engine it hardly even comes out of the housing at all. It also looks like a brand new chain, tensioner, and guides…leading me to believe that somebody either really took care of this engine, or all this stuff has already been replaced. Either way, seeing that these parts look so good I will not be replacing them. Even with no oil pressure at all in the tensioner, turning this engine over counter clockwise does not even attempt to skip a tooth(DO NOT do this unless you know what you are doing). The engine that came out of the car will skip a tooth if the engine is turned counter clockwise as little as 90 degrees (a quarter of a turn). I have a video of this. The intake cam is actually the one that the chain skips the exhaust stays in time with the lower end. 

Why does this matter? The engine never turns backwards so the timing should never skip, right? I believe that it all comes down to force. When the engine is revving up or accelerating there is generally no force on the tensioner, that is because the chain pulls from the opposite side as the tensioner, so it generally just lays up against the chain to keep it from slapping. But when the engine is slowing down or decelerating there is a force in the opposite direction pushing in on the tensioner, and in a way simulating a “counter clockwise” condition on the chain. Of course if the tensioner is functioning properly it will provide an equal and opposite force on the chain keeping it from going slack. So I decided to do an experiment on the tensioner. 

First I just squeezed it by hand, with no oil in it (simulating a dry start), this was relatively easy to do, and accomplished with just my thumb on my left hand. Then I attached the tank shown in the picture below to provide oil to the tensioner. This tank is from Goodson, a machine shop supply company, and is used to pre-lube oil ports on engines that have no distributor. It is basically a propane tank with ports inside of it that you fill with oil, then pressurize to 120 psi with air, hook to your oil port and switch on. I do not think that this is putting 120 psi to the oil port though, but I will experiment more with that this weekend. This does supply oil to the tensioner, and I was thinking that the tensioner should be able to pump up and hold pressure, but the oil just ran out of the little pee hole in the housing. While this was pumping I could just as easy press on the tensioner with my left finger just as before. I have a video of this, if I can figure out how to put it on this forum I will.










































That is all of the experiment that I have been able to do at this time, because I did not have the twelve point torx to remove the cam gears, I could not get the tensioner off. Even though I have a 6, 8, 10, and 12 mm torx, this one is something bigger that I could not find at the NAPA that I work at. But after thinking about it a little, I think that they are the same size as the locking lugs that came on my mk4 GTI, I have not tried this yet though, so I cannot be positive, ill confirm later if it works. But I do plan at some point to remove the tensioner and put 17 psi of oil pressure to it and see what happens. I choose 17 pounds because that is the spec that Mitchell on demand gives. If somebody can give me the psi that there stock engine idles at it would be greatly appreciated, but I will probably be checking it on the new(used) engine in a couple of weeks. I also plan to disassemble the tensioner as much as possible to see exactly how it works. 

Even if the tensioner holds pressure at 17 psi, my experiment showed that the tensioner does not store oil like a lifter does and will not “pump up” if there is oil flowing through it. At this point I believe that there may be no insides to speak of other than a slight spring in the tensioner, they may just be using the small pee hole to regulate pressure in the tensioner. Again I will not know this until at least later this weekend. But if this is the case, if this is what is really happening, then if the engine looses any oil flow or pressure, and suddenly decelerates, then it is possible for the chain to skip. Also if too thin of oil is used then it could run out of the tensioner to fast causing it to have little or no pressure.

I have read on one of the blogs that a guy had a chain skip and bend all of his intake valves after stalling the car out. Stalling the car would cause a sudden drop of oil pressure and violent deceleration. Jamming your car from drive to park could cause this, and just as likely a bad coil pack that causes the idle to jump around could even cause this. 

Again most of this blog is just my opinion of what I have observed with this engine. All experiments are not complete and all data is not gathered. If I find something that proves me wrong I will be glad to post it on here so others do not make the same mistake. Also if anyone who reads this has more experience with these engines and knows something I don’t, please correct me. I will gladly receive any help on this subject.


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## bugwrencher (Nov 8, 2010)

I almost forgot to mention another thing that I though was odd. The guides just slip over the pins in the head, no bolts, clips, nothing but pressure from the chain and tensioner holds them in. I guess that if the circumstances were right one of them could fall out also. Just thought that was worth mentioning.


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## PanzerVW (Jan 9, 2003)

bugwrencher said:


> That is all of the experiment that I have been able to do at this time, because I did not have the twelve point torx to remove the cam gears, I could not get the tensioner off. Even though I have a 6, 8, 10, and 12 mm torx, this one is something bigger that I could not find at the NAPA that I work at. But after thinking about it a little, I think that they are the same size as the locking lugs that came on my mk4 GTI,


I believe it's a 14 or 16mm 
triple square bit- commonly also used on suspension components and brake components:thumbup:
they can be had pretty reasonably$$
helpful site for some of the tools
http://www.metalnerd.com/cat05.htm


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## nothing-leaves-stock (Mar 1, 2005)

the tensioner only has a "piston" and a spring, nothing more. we've had them apart a few time.

if the top guide is gone and the lower tensioner is "bad" it is SORTA possible to skip but not easy. most that we have seen with bent valves are the cam gear slipping after a guide is bad.


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## bugwrencher (Nov 8, 2010)

Okay, I can confirm that the triple squared socket used for the locking lugs on my mk4 is not the same as the cam gear on the 2.5 so it looks like I am going to have to buy one. Does anyone know how to tell if the gear has slipped on the cam? Is there a reference position for the gear to cam that VW originally used? The engine was already out of time when I took the cover off but I do not want to just assume that the gear slipped. I want proof. Should there be markings on the cam or gear when I take it off that show that it slipped? The proof that I have seen so far points to the chain actually skipping, because turning the motor even slightly over in the counter clockwise direction will cause it to skip. However, I am still open to suggestions and reasons for what knocked it out of time. As soon as I get the tool I will pull the sprocket off and look to see what I find.


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## nothing-leaves-stock (Mar 1, 2005)

no, there is no set place for the cam gear to "lock" in. no key way or any tabbed.


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## Unilateral Phase Detractor (Aug 23, 2005)

Some excellent info here :thumbup:


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## thygreyt (Jun 7, 2009)

then, when you put the chain back, how does one knows when it's properly mounted?


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## nothing-leaves-stock (Mar 1, 2005)

you lock the motor in place with correct tools, install chain and tighten gears to spec.


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## bugwrencher (Nov 8, 2010)

*back in*

Okay, Ive put the engine back in, and instead of writing a whole novel about it, Im just going to say that its pretty much the same as taking it out in reverse. But I thought that I would post some new pics of the engine going back together with the trans, and going back into the car. The cars just about done now, just a few things more to hook up and some new oil and a filter and I can start it up. I should get some time to do that next week sometime, then Ill continue with the engine that came out of the car, to see proof of what happened to it, just for curiosity sake. 

also here is a link to the video of me pressing on the tensioner while oil is flowing through it
[video]http://s1120.photobucket.com/albums/l481/bugwrencher/?action=view&current=debbiescamera232.mp4[/video]


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## lilwolf (Dec 11, 2012)

*Engine swap*

I have an off topic type of question....I'm looking into doing an engine swap on my wife's 2000 jetta, now, her car had a vr6 motor in it and my question is, Do you know if it's possible with minimum headache or have you even heard of anyone putting in a 2.5 inline motor in the place of the vr6?


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## toksogun (Mar 24, 2013)

*Engine Swap or just intake manifold replacement*

1) Serpentine belt kept cutting
2) Car started shaking in idle
3) Car shut down completely
4) They fixed it, but car was still shaking in idle.
5) The work they did caused coolant to leak from car and oil to leak from car and car to over heat, catch fire and shut oFf completely
6) They replaced intake manifold w/ new one from china.
7) They used a sealant for the manifold.
8) They supposedly set timing chain and need to test it 

Should I keep pouring money into this car or should I sell it? If I do keep it should I buy a new motor or just a new intake manifold?


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## LVDubn (Mar 14, 2012)

toksogun said:


> 1) Serpentine belt kept cutting
> 2) Car started shaking in idle
> 3) Car shut down completely
> 4) They fixed it, but car was still shaking in idle.
> ...


Holy Old ass Thread! And brought back to life only to be derailed:facepalm: Bro, If I where you, I would start a new thread about your car, describing exactly what the heck you just said. Preferably with a little back story of the vehicle.:thumbup: Just Sayin


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## sneedham6 (May 9, 2010)

Sorry for bumping old thread but I'm starting to consider the engine swap instead of replacing the failed lower chain on my 2010 2.5 Golf.

So no matter what you will need to take off the AC lines to get it through the front? Does that mean the AC needs to be recharged again after?


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