after i got some pistons installed on my motor (gsr), my car start idling at 2000 rpm after the motor is wam. everytime i tap or step on the gas pedal, the rpm goes back to 1000 rpm and jumps right back to 2000 rpm. i changed the throttle body and cable and it still does the same. does anybody know what i can do. a frend of mines say it could be the timing but im not sure, and thought i might ask u guys in here since its a turbo car.

 

check for any vacuum leaks. what ecu injector tb etc. are you using

 

how can i check for vacuum leak? im using some rc 310 injectors, a stock ecu, and a it tb.

 

get carb cleaner spray around the intanke manifold area. If the rpms rise it's because the carb cleaner is being sucked into the engine.

 

It's most likely a vac leak, air in your cooling system, or bad IACV.

 

have you checked your TB gasket? make sure its not upside down

 

if its a vacuum leak shouldn't the rpm jumps up and down?