I recently had somethinf funny start happening on my car. When I shift from park (A4) to drive the rpms drop from 1K to like 5 or 6 hundred and it bounces back and forth (1K to 5 or 6 hundred) for a minute the levels out at 1K. Do you think its the IAC or something else. I recently had the car dyno tuned could it be something in the tables ? or IAC valve because sometimes it will even want to die unless I give it gas.. CAM + LOW RPM = no run ..... so I think its the IAC but before I spend 50 $ on it I want your opinion...Thanks

 

What is your vacuum level?

 

Not sure, guess I should buy a gauge huh ? I have Autotap and the Map ranges from 13.9Hg -> 15.9Hg.. I am going to buy a vaccum gauge, what kind of #s should I look for? and where do I hook it up ? vac for opti, brake booster ect. BTW its a 1997 A4. Thanks

Edit: one more note to consider. You know how us people with A4 and no line lock kinda brake torque it (without spinning tire) to launch. Well when I hold the brake and get the rpm's up to launch and then let off the gas (no launch) it will die, the PCM for some reason can't catch and hold the idle..

IAC PCM help me out guys

 

Any Idea ? Someone........

 

last time and i'll leave everyone alone..need fixed

 

It could be PCM tuning related. My car did the very same thing after I modified the IAC steps vrs MPH follower tables. I had lowered the first values too much.