As your Audi A4 gets older, the parts can get dirtier and dirtier, eventually causing your A4 to seem to have major mechanical problems. When the throttle body is dirty, it can cause your car to have problems accelerating and feel stiff when you first press on the accelerator. You could take it to your Audi dealer, who might charge you more than $100 to do something you can in your driveway for less than $20.
Remove the air duct tube from the throttle body. You will need to unscrew the hose clamps to remove the tube.
Spray throttle body cleaner onto the throttle body, both inside and out. Allow it to liberally cover the throttle body and butterfly valve but avoid the throttle body sensors.
Wipe off the throttle body cleaner using a clean rag. Use a toothbrush to get the smaller areas that the rag cannot easily reach.
Repeat Steps 2 and 3 until the Audi's throttle body is completely clean.
Reattach the air duct hose and tighten the hose clamp.
