Praise be, Think ive found the cure to stuttering/stalling

[Justins145bhpMK1]

OK, now most of you on here will know ive had terrible problems with stalling and missing under acceleration. I have replaced relays, cleaned throttle bodies, replaced coils, lambda's the lot. 2 times on Diagnostic couldnt sort it.

Then today I disconnected my MAF. Ive just driven back to work with a big smile on my face, not a hint of stuttering, goes so much better!!!!!

So I can only gauge that the air mass meter is at fault!!

So who knows if these are repairable as I know they arent cheap!!!

A very happy Justins145bhpmk1

[Justins145bhpMK1]

Can anyone throw any light on repairing the MAF?? the car goes like a rocket now. Much faster than it used to, doesnt idle properly and is thirsty, its fun though!!!!!

[Horney]

Hiya folks..

Just to give you a little heads up on a problem I had with my MK2 8V recently.? Ever since I had the car (1 month) I have had this annoying misfire whilst travelling down the motorway to and from work.? I did the normal things like change the leads dizzie cap, rotor arm etc, but this didn't cure the fault.? I was tempted to change the coil, but as it wasn't failing under load I was reluctant.? I checked the coil at night for the usual signs of 'blue glow' but nothing was seen.

Well last Friday I was bombing down the motorway as usual and the misfire came back again, something triggered in my mind to dip the clutch, blip the throttle a few times and lift the clutch again.? Suddenly the misfire went!? Hmm this is strange... Okay about 5 mins later the misfire came back again, so I did the same.? Same thing happened and the misfire went.? So I knew I could cure the fault by doing this and it only happens at fairly constant speeds.? First thoughts were the MAF (Mass Airflow) which might be giving off spurious readings to the ECU and cutting off the injectors, so at lunchtime I took out the airbox and put it on the bench at work.? Stripped it down and took off the black cover to the MAF and had a look inside.

The potentiometer seemed okay, and I placed an AVO (moving coil meter) across the tracks and moved the airflow trap.? The needle went all over the place, so this was indicative of bad contacts.? Therefore I cleaned the tracks and needles with switch cleaner and tested again.? It was still moving eratically but no where near as bad as before.? There does seem to be some laser cut resistors along the track so it somehow changes the range of resistance when moving from one side of the track to the other.? Also it is in a 'bridge' configuration so the sensor in the air filter side of the network also comes into play.

Anyway I cleaned it all up, re-siliconed the black cover back on and put it back in the car.

BINGO!!!? No more misfiring and the car is running alot smoother.

Not sure if you folks have come across this problem before, but I thought I would add this to the forum for future reference.

Paul..

From "The Garage" forum. I'm going to be doing this this weekend as I think this could be to blame for my problems with my MKII.

[AudiA8Quattro]

Unplugging the MAF can sometimes cause problems, depends on the car.
For example, on my mk3 vr6 the car won't accelerate properly unless it is plugged in.
But on my dad's Audi 90 quattro, i accidently left it unplugged once and the car drove fine, it just kept trying to cut out at idle.
I don't think you can repair MAF's, apparently they can be cleaned. But its probably better to replace it.

[Justins145bhpMK1]

Cheers '6 thought that'd be the case. Im going to swop my MAF with a mates to make sure thats deffo the problem first and then ill get a new one. ?70 exchange from Eur, not bad.

[Horney]

Well I just cleaned mine up (MAF) and refitted it and it seems to be loads better. Gona take it on a nice long run tomorrow and see how I get on.

[AudiA8Quattro]

What did you use to clean it?

[Horney]

Some cleaning solvent spray from the workshop at work and then used a can of compressed air to blow everything out. It would seem however that this has not solved my problem. The car started to miss again when up to temperature on the way into work this morning.

[Overseer]

I read... Unplugging the MAF will cause your CAT to die quicker...

[Horney]

I'm going to get the car up to temp at lunch today, hopefully bringing on the missing fault and then unplug the MAF to see what happens. As I'm running an 87 MKII I don't have a CAT to kill. I'm only posting in here as I'm hoping that whoever fixes their car first might lead to the others fixing theirs.