spdracer53

whenever i start the car cold, i get this weird idling problem where after the rpms drop back down to normal idle (720-780 on my car via the hvac display) my car stumbles and drops in rpms then bounces back up. this only happens after a cold start, and after the rpms are in normal idling range when i'm at a stop does it drop one tick mark down. i've brought this issue up with the dealer and they said they can't find anything that could be causing it. i thought it would be my giac chip, but i swapped it out with an apr chip with stock and chip modes and it did the same thing in both modes.

here are the mods on my car if it helps... 2000 a4 1.8tqm giac chip, bailey dv, scorpion exhaust, vdo boost gauge, greddy turbo timer.

anyone have any other suggestions on what to look for?

Yippers®

find someone local who does MotorVac or BG fuel system cleaning. How old are the plugs?

ModifiedA4

done with vag-com. check the vac-lines and use good gas.

Yippers®

no ICV on the 1.8t and by swapping ECUs he's already done a TBA.

moribundman

Maybe the EGR valve is sticky?

ModifiedA4

didnt know about the icv, but im not talkin about a tba, something in read on the ross tech site.

spdracer53

egr?

spdracer53

and when ever i have brought the car into service it hasn't started off cold so the tech can't see the rpm's drop.

moribundman

The exhaust gas recirculation valve