Very Bad rough and stumbling idle

[Duchenbagen]

I have a 2004.5 1.8T with 17K on it. I am having problem with the idle and the readiness of the car. I have random multiple misfire code and a misfire on all cylinders. I have replaced all coil packs and sparkplugs on the car. I still have the problem. What else is suspect with these motors. I do have a boost gauge and the vacuum and Boost seem to be normal.

[cjonesgo]

Fuel is the next thing to check. As in, "are you getting any?"

Low pump pressure could cause sputtering which could be considered a misfire.

[A4TL]

big ass vacuum leak or maf dying can cause that

i took the N80 valve off and replaced it with a straw (simulating failed open n80) and it did just that misfired every cylinder and made the motor very sad :)

it was just to see what happened. now i know.. vacuum leaks are bad mmkay

[Duchenbagen]

I think that I may have a couple culprits here. I can hear the leak detection pump making weird noises when I start the car cold from a long sit and the N80 may not be working correctly either. All I know is that I have not had any good service up here in Atlanta. If I were back in south Florida this car would go to Champion and it would be fixed right the first time.

[A4TL]

broham you are in the ATL? bring it over i got vag-com.

trust me i just went through this whole ordeal.

having another car to compare and swap parts sure as isht is alot cheaper.


The N80 valve is simple, it clicks when warming up. you unplug both sides car off, blow, no air can move through the n80 when car is off, period, none suck,blow whatever steams your clams.

then turn the car on it will click and when it does you will be able to blow air thru in either direction.

easy test.

then put your finger on the hose going back to the gas tank and it should have about 15-20HG of vacuum if that pump back is good.

other things are check valves.

its easy to test with vag-com because you have tests you can run in basic settings to make it test out instantly so you can see if your changes do squat.

lmk i'm in west midtown- be glad to help a fellow 1.8T B6'ers save a few bucks.

My ride for anything but this problem (heh) goes to (mike) palmer automative 770-425-2549 he charges very reasonable and is a personal friend so i can trust him no matter what the gig is he won't screw over me or my friends.

even the dealer has to hunt this one down the old fashion way but thats fine since it is how you debug problems with old vw's

pm me if you are serious about fixing it. i might need a 12 pack of coke for my time.