So the deal is that my 90 NA s5 will not idle well in gear once warm; the car is fine in neutral but if I put it in gear it will start to sputter and lose rpm. The car will even stall sometimes when left in gear, it will either stall or sputter back up to ~600/700rpm

Any idea on what the problem is? I'm ruling out vacumm leak as the car idles perfect in neutral.

 

You need to push the clutch in or take it out of gear when stopping at lights.

 

Are are you holding the clutch in? Or do you have an auto tranny? Im confused The idle shoudnt change when you are in gear with the clutch pressed down.

 

I know it shouldn't change either, I'm wondering if this has something to do with the accelerated warmup. The accelerated warmup is also dependant on whether the car is in gear or in neutral.