Help! aka My 1.8T A3 is missfiring

[RTAudiA31.8T]

Hi Guys!!! Right, so firstly a little about the car. Its an Audi A3 1.8T 2003 AUM 8l @ 105k miles. I'm having problems with the car miss firing. It starts up fine but when it is put into gear and the clutch is released it starts to miss fire and looses all power, I can sit there with my foot flat to the floor and it does nothing (I have a vid of this but its too large to post). I've had it on a comp and it came up with one code for the secondary air intake. I've taken the pump off and fixed that and replaced a pipe with a 1mm hole in it hoping that this was going to be the cause of the problem and also changed the coolant temp sender. It has been serviced with new oil, filters and plugs (NGK PFR6Q) in the last 1k miles and has also had a Kevlar Clutch made and fitted by C&G Motorsports, but this problem was present before all of this. The problem persists. Now am I looking at new coils? new sensors? if new sensors which am I looking for? The car is alright when warmed up but does hold back slightly under hard acceleration. I don't particularly want to take it to a garage for them to have my pants down and I'm not too bad with a set of spanners so would like to try and fix it myself. Your help would be appreciated. Thanks

[RTAudiA31.8T]

I called the AA out today (don't know why I didn't do it weeks ago!) He disconnected the MAF and the car run fine!!! Looks like a trip to the parts shop tomorrow! Now, the question is, there are so many to choose from £30-£200!!! Which do I go for???

[NickPicks]

usual advice with MAFs is to buy a genuine one. A bosch one might work, but even they are apparently likely to fail prematurely. The cheap chinese ones off ebay are likely to not work at all. Anything other then genuine, you'll be buying twice. Try hoffman car parts to compare their price against your main dealer.

Personally, I've never had to change one, but that would be Crasher's advice, and I'd believe him.

[zollaf]

yes, genuine only unless you like hassle and wasting money. might be worth giving yours a blast of brake cleaner or contact cleaner to see if it helps restore power for a bit. i did one on a skoda last week and it worked, power restored. don't know how long for though but at least i could be 100 % certain that was the fault.

[NickPicks]

I cleaned the one on My wife's A3 with electrical contact cleaner, although I'm not entirely sure it was the cause of the misfire, as it responded better to a set of new spark plugs.

Having a go at cleaning it won't hurt (unless you break the wire / scratch the face, but yours is duff anyway)