Misfire @ 6200rpm?

[Glen Chamberlain]

My mate (PaulUrS4) has a misfire on his AAN S4. It misses every time @ 6200rpm then clears as it revs to the red line. This misfire only occurs in 3rd or a higher gear and only when warm. When cold it pulls strong and cleanly to 7k in all gears. When warm its only ok in just 1st and 2nd? Only fault codes stored are No 1 2 3 4 5 injectors? Naturally I don’t believe there to be a problem with all 5 injectors nor the supply or earths either due to the consistency of the fault at 6200rpm every time? What sensor / sensors are primarily responsible for injector control? Any ideas guys?

Cheers!

[bcdesigns]

i have one urS4 too... log the car on VAGCOM and see the errors... could be this sensor:



that sensor and n-75 didnt arrived yet (i ordered it at 3 weeks) GRRRRRRR

[audiman]

Check for a poor engine earth maybe? Is there an earth strap for the coils on the ABY/AAN/ADU's??? Not too sure, being a 3B owner and all. Also as its temp related check the multi-'mal' function sender in the water manifold. Tests are on www.S2central.net. This sensor can cause all sorts of running problems.

[Glen Chamberlain]

Thanks Guys, I swapped the air intake temp sensor with my ABY any
d its no different. I have checked the engine earths but didnt expect them to be the prob due to consistancy of the problem @ 6200rpm? Temp sensor is next on the list! cheers Guys!

[K7ERG]

Have you checked spark plug gaps as this can cause misfire. Sometimes expand when hot!

craig

[Glen Chamberlain]

Cleande the MAF problem fixed! Oh JOY! wahdda good do!

Cheers Guys!

[blu_s2]

Got to be a sure way to make a $million, Find an alternative deisgn (one that works) for the MAF!

[audiman]

Good work glen