Ive noticed recently that in the morning when turning my car on and putting it in drive or reverse, and just letting it idel (not on accelerator) it tends to jerk me a little and mu rpms go up and down a few hundred. The minute I put my foot on the gas its dive perfectly fine, if after hitting the gas and driving, if i shut it off again and turn it back on it drive perfectly fine when put into drive and just ideling. Anyone know what could cause this? Car has new plugs/wires, dont know about opti. car is an a4 93' formula.

 

Your Idle Air Control (IAC) module might be dirty. Be careful when cleaning it as it's a small motor that is easily damaged. I cleaned mine with a soft brush and you can clean the TB passages with Q-Tips.

Here's a photo of the IAC from Shoebox's site:


http://shbox.com/1/iac3.jpg

 

Thanks could I just spray it down w/ carb cleaner?

 

what plugs did you put in it? if your running a colder plug that could be the issue.

 

I changed plugs like 4 months ago and they have been fine. They are autolite double platinums