# 2.5L fuel filt chg



## snowshoe (Jan 11, 2008)

Just got the Bentley paper manual for the MkV rabbit. It states when changing out the fuel filter on the 2.5L that the fuel system must be properly bled before starting the engine or else catalytic converter damage may result. Special tools are recommended for this procedure: remote fuel pump starter, jumper wire, special fittings for a bleed port on the fuel rail, etc. The manual does mention that VW does not have a recommended changeout interval for the fuel filter. Just a heads up.


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## daemontrym (Feb 13, 2008)

*Re: 2.5L fuel filt chg (snowshoe)*

I never changed a fuel filter on a VW before so bear with me.
I know on most cars they wan't you to depressurize the system before you change the fuel filter. The way that is done is taking your gas cap off and leave it sit like that over night to depressurize it.
I don't really see why you would need to remove the starter and all that stuff. The fuel pump should only be removed only if the fuel filter is in the tank itself.


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## snowshoe (Jan 11, 2008)

*Re: 2.5L fuel filt chg (daemontrym)*

I should have been a little clearer. The bleeding procedure is after the fuel filter has been changed. This it to remove any air entrapped in the fuel line and new filter. Apparently, this is not required with the 2.0T.


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## spitpilot (Feb 14, 2000)

*Re: 2.5L fuel filt chg (snowshoe)*

I've never seen a bleeding step in replacing a fuel filter B4...and I've changed filters on cars ranging from Alfa Romeo..thru BMW...to Volvo and Volkswagen for years..make that decades!







I'm havin a hard time understanding how a little air in the fuel system can cause cat converter failure...I know dumpin unburned fuel into the cat causes it to overheat and fail (that;s why the CEL blinks whenever you get consistent misfire trouble code)...but air?..maybe some factory trained VW wrench will chime in on this. Looks to me like you could jury rig up a remote fuel pump switch ez enuff and probably figure out somethin to go on the fuel rail to catch fuel while you run pump a few moments to force air outa the system. As far as change interval..VW magically change fuel filter to "lifetime part" back in the 90's..even though other car makers using same Bosch filters (BMW and Volvo) continued to say they should be changed at around 50K miles...I'm plannin on doin that with the Rabbit...I've changed my MKIII Golf fliters and Passat filter every 50K (just like I changed the filters on previous VW's I've owned). http://****************.com/smile/emthup.gif


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## spitpilot (Feb 14, 2000)

*Re: 2.5L fuel filt chg (spitpilot)*

Do you know if the fuel rail fitting is a standard "schrader valve" set up? If so..looks like the Acton CP7838 fuel pressure tester rig would do the bleeding job as well..(it has a bleed off hose attached to the meter base)..this tool is on sale right now at Amazon.com for $50 with free shipping. I'm gonna check on the fuel rail fitting tomorrow and if its indeed a schrader valve set up I'm buying this tester....not only can you change fuel filter but you can monitor fuel presssure...take reading now when everything is A-OK and then you'll have a "baseline number" to compare with if you suddenly get rough running and measure pressure again! I'm sure dealer would charge way more than $50 labor to change filter so I'd come out ahead if I only used it once!...Not to mention I won't be payin dealer list for the filter part price!


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## snowshoe (Jan 11, 2008)

*Re: 2.5L fuel filt chg (spitpilot)*

splitpilot,
Forgive my ignorance, but I'm not familiar with a schrader valve. I did stumble upon this VW (05-08 Jetta diesel?) fuel system bleeding procedure online - it shows the same fitting (VAG 1318/20):
http://www.keepandshare.com/do...&da=y
This procedure is very similar to the one in the new Bentley paper manual for the 2.5L Rabbit engine, except for activating the pump through the diagnostics port. The new manual does not describe the mechanism for catalytic converter damage, but I would quess there is a chance of misfire due to entrapped air.

_Modified by snowshoe at 9:56 AM 1-3-2009_


_Modified by snowshoe at 10:11 AM 1-3-2009_


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## Audi4u (Jun 29, 2002)

Its really easy to bleed. There is a bleeding valve on the fuel rail. 
If you don't bleed the system it takes a very long time to start. 
I don't see it leading to catalytic converter damage though.


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## rangerbrown (Jul 12, 2007)

were is the filter located any way? in it under the car or under the hood. i havent really looked around for it yet,

i was told by a vw tech that 40k was to time change the filters and plugs


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## Audi4u (Jun 29, 2002)

It's located underneath the car. below the fuel pump.


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## spitpilot (Feb 14, 2000)

*Re: 2.5L fuel filt chg (snowshoe)*


_Quote, originally posted by *snowshoe* »_splitpilot,
Forgive my ignorance, but I'm not familiar with a schrader valve. I did stumble upon this VW (05-08 Jetta diesel?) fuel system bleeding procedure online - it shows the same fitting (VAG 1318/20):
http://www.keepandshare.com/do...&da=y
This procedure is very similar to the one in the new Bentley paper manual for the 2.5L Rabbit engine, except for activating the pump through the diagnostics port. The new manual does not describe the mechanism for catalytic converter damage, but I would quess there is a chance of misfire due to entrapped air.

_Modified by snowshoe at 9:56 AM 1-3-2009_

_Modified by snowshoe at 10:11 AM 1-3-2009_

Schrader valve is the type of valve used on tire valve stems, and AC fill ports...the fuel pressure tester I found says it works on all cars with either "banjo fitting" or schrader valve pressure ports on the fuel rail...from the picture in the Bentley...this VW set up looks like a Schrader valve hook up...so this would work...If you wanna live dangerously you could just take a pick and press the core of the fuel schrader valve down while you run fuel pump with a remote switch (just unplug connector in trunk/hatch and connect up remote switch to power pump)..but that would squirt fuel all over...definitely want to do that outside where there is no ignition source like a pilot light on your water heater etc!





















I've seen a car catch fire from working on fuel line without disconnecting battery (tool touched alternator terminal..spark lit off the gas)..it was NASTY...so I'm gonna get one of these testers..$50 is cheap if you avoid fire hazzard! http://****************.com/smile/emthup.gif


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## snowshoe (Jan 11, 2008)

*Re: 2.5L fuel filt chg (spitpilot)*

Thanks for the replies. This seems very doable. However, I do have a question about connecting the remote switch to the fuel pump. The diagram (M20-0252) in the new Bentley manual for the 2006-2009 Rabbit shows a 5-pin (male) connection on the fuel pump. To connect the remote switch, one connection goes to the + terminal on battery and the other connection is to terminal 1 pin (of five) on the fuel pump. A jumper wire is then used to connect terminal 5 pin of the fuel pump to terminal 5 (female) of the 5-pin harness connector. Can someone explain the jumper connection?








The VAG kit/adapters/wires shown make all the connections very easy - is there a source fo the VAG stuff in the US? Can a dealer order these?


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## mk2core (Oct 31, 2006)

*Re: 2.5L fuel filt chg (snowshoe)*

um..... i changed my filter with no problems... didn't bleed anything.


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## spitpilot (Feb 14, 2000)

*Re: 2.5L fuel filt chg (snowshoe)*


_Quote, originally posted by *snowshoe* »_Thanks for the replies. This seems very doable. However, I do have a question about connecting the remote switch to the fuel pump. The diagram (M20-0252) in the new Bentley manual for the 2006-2009 Rabbit shows a 5-pin (male) connection on the fuel pump. To connect the remote switch, one connection goes to the + terminal on battery and the other connection is to terminal 1 pin (of five) on the fuel pump. A jumper wire is then used to connect terminal 5 pin of the fuel pump to terminal 5 (female) of the 5-pin harness connector. Can someone explain the jumper connection?








 
The jumper is to carry ground connection over from the connector you remove to the pump ground terminal so when you bring +12V to the "hot" terminal of the pump (pin 1) pump will run. The other pins are for fuel gauge sender signal....same set up as in my ol Golf III. http://****************.com/smile/emthup.gif http://****************.com/smile/emthup.gif


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## carlos_31820 (Jul 23, 2006)

*Re: 2.5L fuel filt chg (mk2core)*


_Quote, originally posted by *mk2core* »_um..... i changed my filter with no problems... didn't bleed anything.



Did it take a long time to crank? I'm trying to decide on buying the ECS 40k kit. My dealer wants $620 (after tax) for the 40k service.
The fuel filter change is the only thing I'm uneasy about.


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## NaKoRuRu (Jun 5, 2005)

Lots of good info here. I'm coming up on my 40k as well and like the person above me, I am not to confident in changing the fuel filter. Can someone post a DIY if you have actually performed it yourself? Please? Pretty please?








Also, according to VW.com fuel filter is not on the "to do" list for 40k. But I have always read somewhere/known that it was supposed to be changed at 40k. Any ideas what thats about? Linky: http://www.vw.com/myvw/yourcar...en/us/


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## spitpilot (Feb 14, 2000)

*Re: (NaKoRuRu)*

Fuel filter for 2.5L cars has pressure regulator built in...you have to disconnect 3 lines..input, output and regulator return line. Disconnect clamp holdin filter to body..and remove...reinstall filter. Then if you wanna "go by the book" you're supposed to bleed air outa the filter..you do that by connecting a switch to the # 1 pin of the pump connector (under cover in trunk/hatch area) and ground to pin 5...connect switch to battery + and you can run the pump w/o turing on the starter etc. There is a fitting on the fuel rail..which I believe is a schrader valve (like in a tire)...you can buy a tire chuck with a 1/4" tubing barb on one end..connect some tubing to that to take fuel you're gonna bleed out to a pail an you're good to go. Just start pump with your switch and press chuck onto the pressure port on the fuel rail..the schrader valve will open and you'll bleed out air, put cap back on pressure port, reinstall engine cover and you're good to go..or pay dealer for 1 hour labor to change fuel filter (dealer here charges $130/hour so you know I won't be goin that route when I hit 40K miles!). http://****************.com/smile/emthup.gif 
PS: Do this process outside away from sources of ignition..you don't wanna spray gas into a bucket next to your waterheater in the garage!


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## carlos_31820 (Jul 23, 2006)

Found this online...
http://www.keepandshare.com/do...&da=y
I'm trying to figure out how exactly one could damage the catalytic converter by not bleeding the fuel filter. I'm almost leaning towards not replacing the fuel filter on the 40k service. Seems like a PITA and I'm not even seeing it on my Bentley service schedule.


_Modified by carlos_31820 at 7:34 PM 1-5-2009_


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## carlos_31820 (Jul 23, 2006)

*Re: (spitpilot)*

spitpilot... did you see this one? Looks much like the Actron unit but a little cheaper...
http://www.amazon.com/PROFESSI...uto_1


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## snowshoe (Jan 11, 2008)

*Re: (spitpilot)*

splitpilot, thanks again for your help!
It would be nice if the aftermarket (ECS are you listening?







) put together a little kit (remote switch with proper adapter to connect to pin #1, custom fit jumper wire for ground to pin #5, schrader valve fitting with hose barb, and gas resistant tubing) to carry this out.


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## carlos_31820 (Jul 23, 2006)

*Re: (snowshoe)*

Can't we make the pump run using Vag Com output tests for the Engine controller? I took my laptop in the garage and did the engine output tests and I could hear the fuel pump priming as it does when you open the car door in the morning. I'm wondering if the output tests could be an alternative to this wiring and switch madness. After all, the Bentley procedure seems to indicate the VW techs prime the pump using the VAS software.


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## ~kInG~ (Jun 8, 2005)

*Re: (carlos_31820)*

what about just opening the door a few times (with the fuel rail valve open) so the fuel pump primes the system?


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## carlos_31820 (Jul 23, 2006)

*Re: (~kInG~)*


_Quote, originally posted by *~kInG~* »_what about just opening the door a few times (with the fuel rail valve open) so the fuel pump primes the system?

Not sure that would work. In my car, it only primes once. It won't do it again if you keep opening the door.


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## spitpilot (Feb 14, 2000)

*Re: (carlos_31820)*


_Quote, originally posted by *carlos_31820* »_spitpilot... did you see this one? Looks much like the Actron unit but a little cheaper...
http://www.amazon.com/PROFESSI...uto_1

 Looks like that would work fine on the 2.5L....it doesnt have "banjo fittig" adapters which may be needed on some other car down the road...I think I'd spring for the extra $15 to get those..never know what car you might need to work on later. http://****************.com/smile/emthup.gif


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## spitpilot (Feb 14, 2000)

*Re: (carlos_31820)*


_Quote, originally posted by *carlos_31820* »_Can't we make the pump run using Vag Com output tests for the Engine controller? I took my laptop in the garage and did the engine output tests and I could hear the fuel pump priming as it does when you open the car door in the morning. I'm wondering if the output tests could be an alternative to this wiring and switch madness. After all, the Bentley procedure seems to indicate the VW techs prime the pump using the VAS software.

Yes you can run pump thru the VAG if you have VAGcom set up..for those of us who don't...the switch 'n wire is fast and cheap...done this for years to test fuel pump output..VW used to tell you to put a jumper and switch on the fuel pump relay socket to do this but I guess they switched gears here and went to direct connection at the pump leads 'cause acces at the rear is ezier than to get at the relay panel. http://****************.com/smile/emthup.gif


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## spitpilot (Feb 14, 2000)

*Re: (carlos_31820)*


_Quote, originally posted by *carlos_31820* »_ I'm almost leaning towards not replacing the fuel filter on the 40k service. Seems like a PITA and I'm not even seeing it on my Bentley service schedule.

_Modified by carlos_31820 at 7:34 PM 1-5-2009_

VW somehow magically transformed the fuel filter into a "lifetime" part back in the 90's..B4 that they reccomended changin 'em out at about 30K miles. Other mfgs who use the same Bosch filters (BMW, Volvo etc.) continued reccomending routine change out....Why did VW do this??...I'm thinkin it was to reduce "cost of ownership" and look better in Consumer Reports..plus if the car starts havin issues after 3 years or so..if your a leasor you don't ever see em..and if you still have the car you start thinkin.."car's gettin old..gotta start lookin at new ones"..which is just what VW wants you to do!






















Preventative maintenance is done to prevent breakdowns..you can do it or "fagetaboutit"...and wait for something to break...just don't whine to us about "gee it was pouring rain/snowing etc..and the @#$$% car wouldn't start"...."Took it to the dealer and they said the fuel filter was clogged..they see it often on cars with over 50K miles."...You can replace stuff on your own schedule and by buying parts online cheap and save tons of $$$ and wasted time waiting for tow trucks etc..or you can wait till something breaks (serp belt, timing belt, radiator hose etc.) and pay big bucks and be way inconvienced (You just know its gonna crap out on Sunday late 50 miles from home!







).... Your call....I'm goin with PM all the way..have saved tons 'o money over the years and never been stranded on a Sunday!


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## carlos_31820 (Jul 23, 2006)

*Re: (spitpilot)*


_Quote, originally posted by *spitpilot* »_Preventative maintenance is done to prevent breakdowns..you can do it or "fagetaboutit"...and wait for something to break...just don't whine to us about "gee it was pouring rain/snowing etc..and the @#$$% car wouldn't start"....

Chill, man. I agree with you on the PM. The fuel system bleeding seems like a pain in the neck. That's all. I'm just unfamiliar with it and thus, hesistant to tackle it and screw something up in the process.


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## ~kInG~ (Jun 8, 2005)

*Re: (carlos_31820)*


_Quote, originally posted by *carlos_31820* »_
Not sure that would work. In my car, it only primes once. It won't do it again if you keep opening the door.

open, close, open, close, open, close!!!!


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## carlos_31820 (Jul 23, 2006)

*Re: (~kInG~)*


_Quote, originally posted by *~kInG~* »_
open, close, open, close, open, close!!!!









Does yours keep priming repeatedly when you open, close, open, close the door? Mine doesn't.
BTW - Boricua, yo soy de San German. (I'm from San German, PR).


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## ~kInG~ (Jun 8, 2005)

*Re: (carlos_31820)*


_Quote, originally posted by *carlos_31820* »_
Does yours keep priming repeatedly when you open, close, open, close the door? Mine doesn't.
BTW - Boricua, yo soy de San German. (I'm from San German, PR).

Dunno, I'm going to try and do this tomorrow.
Happy Triking day! Feliz Dia de Reyes!!!


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## spitpilot (Feb 14, 2000)

*Re: (carlos_31820)*


_Quote, originally posted by *carlos_31820* »_
Chill, man. I agree with you on the PM. The fuel system bleeding seems like a pain in the neck. That's all. I'm just unfamiliar with it and thus, hesistant to tackle it and screw something up in the process.

I'm "Chilled"...its the guys who %#[email protected]%# at their cars and VW etc after doin nothin but put gas in the sucker an drive that need to chill! LOL...The bleeding can't be all that tough...not like doin brake fluid flush for sure..there's a fitting on the fuel rail to bleed air out...what I need to do is look at it..from what I've seen in Bentley drawings it looks like a standard "schrader valve" (threads outside little pin valve inside ...look at your tire fill stem)..if that's the case just using an air chuck fitting with a lenth of tubing to carry gas away from car and into a catch can should be all you need to do this safely..just do the "remote swich" or VAG to run pump for a few seconds. Still not convinced that its necessary..never seen that required B4 and I've read fuel filter changing proceedures for lots of cars....engine might misfire a few times due to weak mixture while air is in system, but that's gotta come out quickly and a few misfires won't fry a Cat otherwise everyone who waits too long to replace plugs would be buying new Cats and I don't see that happenin..you know guys would be complaining about havin to buy $1000 cats 'cause they left plugs in there for 60K miles and had a few misfires!


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## carlos_31820 (Jul 23, 2006)

*Re: (spitpilot)*

Ordered the 40k kit from ECS so I'll post back with my findings on the fuel filter bleeding.


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## zakattak (Apr 28, 2007)

*Re: (carlos_31820)*

i do my fuel filter every year. it is easy, requires no special tools, and took me 15 minutes with a lift. to prevent the difficult restart you can turn the key on and off without starting the car to prime the fuel pump. 
i've never bled air, and am curious as to why i would need to.








i have never had a problem or a MIL.


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## spitpilot (Feb 14, 2000)

*Re: (zakattak)*


_Quote, originally posted by *zakattak* »_i do my fuel filter every year. it is easy, requires no special tools, and took me 15 minutes with a lift. to prevent the difficult restart you can turn the key on and off without starting the car to prime the fuel pump. 
i've never bled air, and am curious as to why i would need to.








i have never had a problem or a MIL.
 Only reason I can think of for havin a bleeding step in the MKV filter change is that there is a pressure regualtor incorporated into this filter...still not sure why omitting bleeding could damage CAT????


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