I need some advice from the Mustang side of Ford!
I just completed a conversion to EFI mass air on by 76 Bronco with thing going well. Well til now. The truck starts fine but idles a little rough, and doesn't get better when warmed up. It skips like it running on 6 cylinders when accelerating from any speed and a real lack of power.
I read the codes with nothing unexpected. Fuel pressure is 34 psi and steady. I tested the spark at each cylinder and they are very healthy. I looked at each plug and they all look to be firing - suggesting no clogged injector. Base timing is 10 deg BTDC. I removed and reinstalled the upper intake - looking for vacuum leaks.
New parts: efi harness, idle bypass, fuel pressure reg, plugs, wires, cap, rotor, coil, BR sensor, vss, air and temp sensor.
Possible symptom: I did a vacuum test which was steady but maybe low - 14 to 15 inches at idle. Shouldn't it be 20 inches?
I advanced the timing a little (14 Deg) no improvement.
It ran considerably better when first completed. Don't know what has changed? Any ideas. Valve timing? Could have I pumped a tooth on the timing chain?
Thanks
I just completed a conversion to EFI mass air on by 76 Bronco with thing going well. Well til now. The truck starts fine but idles a little rough, and doesn't get better when warmed up. It skips like it running on 6 cylinders when accelerating from any speed and a real lack of power.
I read the codes with nothing unexpected. Fuel pressure is 34 psi and steady. I tested the spark at each cylinder and they are very healthy. I looked at each plug and they all look to be firing - suggesting no clogged injector. Base timing is 10 deg BTDC. I removed and reinstalled the upper intake - looking for vacuum leaks.
New parts: efi harness, idle bypass, fuel pressure reg, plugs, wires, cap, rotor, coil, BR sensor, vss, air and temp sensor.
Possible symptom: I did a vacuum test which was steady but maybe low - 14 to 15 inches at idle. Shouldn't it be 20 inches?
I advanced the timing a little (14 Deg) no improvement.
It ran considerably better when first completed. Don't know what has changed? Any ideas. Valve timing? Could have I pumped a tooth on the timing chain?
Thanks
