04 A4 1.8TQ 92K miles. Solid CEL
Random misfires. Stumbling idle. Lean codes. Cleaned MAF, cleaned AIT, swapped recalled coils around, swapped in the old plugs. No change in behavior. You really can't feel it while driving, but you can feel the misfires while sitting.

I'm guessing vacuum leak somewhere. All of the hoses look good that I can see. PCV is surprisingly clean for 92K miles.

The only variable is that I do not know if the dealer replaced the fuel filter when they did the pump a little while back. I have one ready to go though.


Anybody know of any common failure points for the vac system on a late model AMB 1.8T B6 A4? It's got way more lines than my AWM of the same year.


Everything is bone stock, right down to the new PFR6Q plugs. There are no performance mods whatsoever to this car. I've even done a TBA. I need to scan again tonight. The wife has not noticed a drop in trip mileage either.

Maybe it was my computer, but I would be in the middle of clearing or scanning for codes and I would get a controller error. Worked fine at first.


Wednesday,15,September,2010,18:49:47:07200

VCDS Version: Release 908.2



Address 01: Engine Labels: 06B-909-518-AMB.lbl

Control Module Part Number: 8E0 909 518 AK HW: 8E0 909 018 A

Component and/or Version: 1.8L R4/5VT G 0004

Software Coding: 0016751

Work Shop Code: WSC 63351 000 00000

6 Faults Found:



16684 - Random/Multiple Cylinder Misfire Detected

P0300 - 008 - Implausible Signal - Intermittent

16686 - Cylinder 2: Misfire Detected

P0302 - 008 - Implausible Signal - Intermittent

17658 - Fuel Level too Low

P1250 - 008 - Implausible Signal

17544 - Fuel Trim: Bank 1 (Add): System too Lean

P1136 - 001 - Upper Limit Exceeded - MIL ON

16891 - Idle Control System RPM: Higher than Expected.

P0507 - 001 - Upper Limit Exceeded - Intermittent

17519 - Oxygen (Lambda) Sensor Regulation: Bank 1: System too Lean

P1111 - 002 - Lower Limit Exceeded - MIL ON

 

sound slike a vac leak. check ur check valves. If they are corrided they will lose vaccume and cause misifre. Or check for cracks in the system also.

 

Thanks. All check valves that I have located are pristine. I have an idea where the breakdown might be. The piping off of the oil filter bracket. Possibly the "T" where the bleeder valve is. I didn't get a good look, but I saw some oily build up on that pipe that goes into the bracket.

 

the one under the manifold is a pain.

 

yeah, I know. Luckily, I have small hands and am a bit of a contortionist.

 

Well, I found it. It's gonna be a bitch, but at least I know now.

It's #2 in this pic, but the end going to the "T" is female, not male.

Anybody have access to ETKA for an Audi A4 late model AMB with this kind of bleeder valve (06A103245F)?

 

Man, I can't win. The hard tube from the back of the VC to the Bleeder valve was cracked too. DIY replacement since it's the weekend. Confident that was all fixed. Still running lean. oy

 

could still have a small leak somwhere. . did u cleared ur codes and drive around a bit and the light came back on.

 

Yup, light back on after I cleared it. Rough idle too. Throttle body adaptation was OK. What stinks is that the closest shop, NGP, is getting ready for H2Oi and I probably won't be able to let them look at it till next week. At least it runs kinda ok.

Gotta pressure test it here soon. Also going to swap my puck valve out with my passat 1.8T one to rule that out. I probably need to install a new fuel filter. I thought they might have done it under warranty with the fuel pump (I would) but I bought one anyway and hope to install this weekend. I bought it at 17K miles and now has 93K so I know I've never done it.

 

It was the 3 way bleeder valve. Only thing I have to clear up is the dip in RPM when coming to a stop. Pulls nice and strong and idles perfectly now. Need to clear and scan for more codes now.