Hi all,
I have an 86 cutlass supreme 3.8 v6 3 speed auto. If I accelerate hard, 3/4+ throttle, or the car downshifts to 2nd going uphill, the engine will begin bucking, jerking and losing power around 50 mph. If I lock it in 2nd gear I can slowly take it up to 60 mph with no trouble and I can hold it on the floor while dragging the brakes and it runs fine. This only happens at higher rpm AND near full throttle. Once it starts losing power, throttle position becomes irrelevant; I can leave up on it some and it will keep jerking. The only way to get it to stop is to let it go back to idle for about 3 seconds and then it runs fine again.
I replaced plugs, wires, cap and rotor about 6 months ago before this started. Fuel filter was replaced 2 years ago. I have tried a new coil, fuel pump and 02 sensor. No CEL. Anyone have any ideas?
I have an 86 cutlass supreme 3.8 v6 3 speed auto. If I accelerate hard, 3/4+ throttle, or the car downshifts to 2nd going uphill, the engine will begin bucking, jerking and losing power around 50 mph. If I lock it in 2nd gear I can slowly take it up to 60 mph with no trouble and I can hold it on the floor while dragging the brakes and it runs fine. This only happens at higher rpm AND near full throttle. Once it starts losing power, throttle position becomes irrelevant; I can leave up on it some and it will keep jerking. The only way to get it to stop is to let it go back to idle for about 3 seconds and then it runs fine again.
I replaced plugs, wires, cap and rotor about 6 months ago before this started. Fuel filter was replaced 2 years ago. I have tried a new coil, fuel pump and 02 sensor. No CEL. Anyone have any ideas?
