Unusual miss fire

[Sparesoft 0]

Hi all,

Last couple of days my VR has been having a a strange miss fire/coughing fit , from cold it drives fine and seems until it gets up to temperature, then it starts to miss fire badly and lose a load of power for a couple of miles, then it will be fine again after that for the remainder of the drive.

Plugs and leads are only 2 months old and I've already checked and the coil pack is only a year old and still looks in good condition (that surface is stil intact and not arcing onto the case from what I can tell).

Can anyone suggest what the problem might be or had the problem before?

Many thanks

Baz

[russj249 2]

It could be a couple of things really.. air flow meter would run like that if it was faulty, but that's not a misfire, just a complete fueling mess so runs.lumpy with no throttle response.

Also could be an engine coolant temp sensor or similar

Ideally you need to get it on vag com and get the fault codes checked out.

[Sparesoft 0]

Happy to report that despite not having access to a vagcom computer, i decided to have a quick check of the MAF while i was fixing other bits and bobs, and it appears that the filliment in the sensor was abit broken, so after a quick replace (picked up from GSF for £65) and a good blat around town, all seems to be good

Many thanks on some good advice.

[Sparesoft 0]

Ok, update time.

the after i changed the MAF it started doing it again, so i got the bad boy up on the ramp and changed the Lamdba sensor (knew that was on the way out anyway as had a previous code for it) but the was still no difference.

Took it to a vag specialist yesterday and left it with them. Later that day they called back and despite taking it for a good drive round and vagcom ing it they could re-create the fault or find anything wrong with it.

So i went to pick it up this morning, drove it home and it started doing it again, stopped for petrol as it was nearly empty, started it up again and it was gone, drove around for about an hour and it didn't come back once.

So it only seems to be happening from a cold start, if i stop it and start it up again once it warms up it seems to go back to normal.

What could be causing this?

[Biggazvr6 0]

Coolant temp sensor is a cheap try. Couple of quid from gsf or tps etc. See as it's only from cold and that it's a warm/cold issue that would be my bet.