The car will start, and the idle will start hunting(1500-2000). It's a very strong, as if you were to floor the accelerator, than turn the key off. When I try drive it, it'll surge badly durring the transition from accel to decell. When I come to a stop and let the car idle, it will only run on one rotor. Even when I rev the motor, and pull away from the stop sign, the other rotor won't "catch". The car is getting fuel, because when it's running on one rotor you can hear it back firing badly. I have tried replacing the AFM, coils, plugs, and wires, and it still acts the same. Also I have checked the compresion, and it's OK.

When it is very cold (under 10) the car will run on one rotor for about 20-30 seconds after startup, then it would "catch" and run normally.

BTW-it's an S4 na

 

check and adjust the TPS