A3 1.8 T Running rough on startup - and Idle bouncing whilst standing - please help

[Jeff321]

Hi guys once again i have purchased a a german 1.8 T car, last time i owned a vw golf gti turbo and it was amazing, i have decided to now buy a a3 1.8 T on a 2000 model (X ) reg, it is a great car however on cold startup iot runs very rough and misses until it you rev it up a little, then however when it is up to operating temperature the revs bounce below 1000 rpm, i have got a elm 327 diagnostic cable however dont have any software for it so cannot really do much diagnostic work myself, however i was told one of the coil packs may be faulty so i purchased one and kept changing it trying to distinguish which one is fault however it didnt seem to make any difference as the revs were still bouncing up and down, bow i have taken the new coil pack out, serviced the car with new oil and spark plugs and have decided to clean the body throttle as that may be sticking and causing the revs to bounce up and down whilst idling, i havent really owned an audi before and dont know too much about them and would be really grateful if somebody could shed some light on what to inspect or provide some info or links to some software which may help me distinguish the fault as i have previously spent money trying to fix things and it has never really worked out well and had replaced the wrong parts costing lots of time and money.

Thanks guys hope to hear from you soon any help, advice or input is gratefully appreciated.

Regards

Jefg

[Lofty79]

Throttle body will need a clean. remove it unplug it etc and you will see alot of thick black gunk on the engine side scrape it away and then clean it thoroughly even on the edges of the butterfly, you will have to twist it. toothbrush all around it until it is nice and silver. That will be it mate sorted. Petrol/carb cleaner/thinner etc

Make sure all dry and cleaning solution removed or shell rev her **** off

sorry just re read and saw you already did throttle body, i was sure that would sort it, sorry

You could unplug MAF sensor and see if it still does it. If not reconnect, and then do coolant temp sensor unplug and start up again, may diagnose one or both of these sensors

[Crasher]

i was told one of the coil packs may be faulty

Whoever told you that was an idiot! Get a fault code read carried out before you waste any more time and money.

[Jeff321]

hi guys thanks for thew replies turns out it was the throttle body which was dirty, git some carb cleaner and cleaned it out thoroughly with a tooth brush and vwoilaaa its sorted no more rough start, no more revs bouncing up and down, and best of all no more stalling the car ) thanks forthe input guys i really do appreciate it

[Lofty79]

thought so