vair_17

repost from the 4000/coupe forum in hopes of different answers

i tried to re-move the thermostatic control valve in the air box to do a mod..but i decided it was to big a job for just me so i put it back in.. i removed most of the top of the air box and when i put it all back in i took the audi for a spin and the rpm`s where jumping up and down about 800 rpm and when i came to a stop it was at like 1800-2200 rpm and i just took it home.. anyone have any ideas...

ps. anyone know what way the valve is suppose to be. hot or cold i have a feeling that is the problem

shawfm

Idle Stabilization Valve. Next thing that comes to mind is that you may have created an leak on the intake system after the airbox and are now sucking in un metered air which would also cause your symptoms