duvalsoldier904

other day i was sitting at a red light and all of the sudden the car just dropped to about 100 rpms and would bounce between 100-500 rpms and sounds like its about to stall out i drive an a4 and it seems to not happen everytime tough and it has happen about 3 times in the past 2 days any ideas of what it could be?

wssix99

iTrader: (5)

Does it happen when you are shifted in to Neutral?

duvalsoldier904

no only when im in drive but i think i figured it out. i think its my maf gone bad

LS6427

iTrader: (2)

Don't see how a MAF can cause a rough idle AFTER its up to operating temp.

But I guess you never know with these damn cars.....

I'd say IAC or failing 02 sensor.

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wssix99

iTrader: (5)

If the problem doesn't happen when you are in neutral, then it probably has something to do with your transmission. How many miles does your torque converter have on it?

duvalsoldier904

Well I didn't think it would be an o2 sensor because I've been driving with out them working since I put headers and I thought of the Maf becuz that and on o2 code was thrown when I put it on a code reader

duvalsoldier904

And with the torque converter I have no idea if it was ever replaced before I got the car but the car has 99,000 miles on it and I but about 10,000 on it

my bandit

iTrader: (10)

wouldnt the iac throw a code? his only codes were his MAF and the o2 sensor. one of his o2 sensor wires is completely burnt through since the installer didnt ziptie it right.

LS6427

iTrader: (2)

Our PCM's don't throw codes for allot of things, and some PCM's won't throw a code until a part is 100% failed. My PCM doesn't show codes for bad 02 sensors, a bad crank shaft position sensor and a failed TPS sensor. WHY....I have no idea.

These PCM's are good.....but they are also complete crap. Not everyones PCM is the same, some act totally different than other peoples. My friends 2000 Camaro SS pops codes for every damn thing.....mine doesn't. Wierd.

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LS6427

iTrader: (2)

I can tell you this too.....our MAF's, at least on my car.....have something to do with our auto trannys and how they operate. When my PCM was failing and it completely took my MAF out of the system, my tranny was banging into gear when I would go from PARK to REVERSE or a DRIVE gear. After I got that all taken care of and the MAF came back into the loop, the banging was gone.

Just saying.

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wssix99

iTrader: (5)

The next time this happens, try two things:
- Shift to Neutral and see if the problem goes away. If so, its probably the torque converter.
- Take your foot off the brake and see if the car creeps forward more than normal. If so, it again points to the torque converter.

Depending on how the car has been driven, its not unheard of the torque converter going bad - I'd think 100k is a little early, though.