2.8L 12v bad idle

[ThatGUY]

I have a 12v AFC with a complete refresh.

I start it up and it runs great; for a few minutes then is gets lumpy and throws a check engine light.

If I start it and immediately get on the motor way it will cruise between 60 and 80 without any issues. Once I pull off the road it takes about a minutes before the CEL comes back on and rough idle again.

I do not have a vagcom... but the blink code is for a Lamda.

I have a new MAF and 2 new lamdas
new plugs

I tested all vacuum lines. The only one that didn't hold vacuum was the EGR solenoid (but I'm unsure how that works)

Any ideas will be greatly appreciated.

Andrew

[ThatGUY]

I know this forum is primarily for the S2/RS2... the reason I post my question on this forum is because the people here a very knowledgeable. Besides this is my #1 place on the Internet.

So after checking and chasing everything I could think of I could hear excessive air from around the brake booster (vacuum). I disconnected the feed line from the IM and plugged it up. no more check engine light and idle is almost perfect.

With that being said I also have a braking issue. I have a very firm pedal but probably too firm; and the car doesn't stop the way it use to.

I may be able to solve both my problems with one part.

Andrew

[ThatGUY]

I hope my problem will be an easy fix... While my engine was out I also upgraded the brake master cylinder to that of an S4 which is the same on the ABY 441611021B.

I didn't know the vacuum assist worked, I just swapped the brake master cylinder over without a gasket or O ring between the two. Since the S4 which it came off has hydraulic assist there is no gasket.

I know there are people interested in changing their brake systems over to vacuum; maybe my mistake will help someone.