we just dropped in an ls in my eg and every time i put some gas it, it makes a low flapping noise. u can hear it if u turn off your radio. it doesnt flap when im not pressing the gas. the flapping gets faster when you put more gas in it. has any1 have this problem b4?

 

Is it throwing any codes? Did you compression test the motor? What is the ignition timing set at? Did you check the timing belt to see that the cam timing is correct?

 

right now im running on the old ls ecu(obd-1) jux for right now. and we did check the timing belt, etc