1991 Ford Mustang Grounding properly?

KIM SHERWOOD

MEMBER
1991 FORD MUSTANG

Engine Mechanical problem
1991 Ford Mustang 4 cyl Two Wheel Drive Automatic

Make a long story short. Switched out motors with same size and year from a Ford Ranger. All okay, but won't start. Spray eather in intake and runs about 3 sec. Tries to turn over. Fuel pump kicks on, 40 lbs. Pressure. Injector plugs are getting electricity. Regulator is getting fuel. Thinking that somewhere it's not getting ground. Checked the timing, it was good. I just doesn't seem to be getting fuel. Is it possible that something within the PCM or a bad relay. Is there anything that you could suggest to check. We took the wire harness off the car's original motor and hooked to replaceing motor. Made sure the replacing motor had all the same sensors that fit the original harness. This is a teen boys first car and he can't afford much so trying to do as much on his own as can. Very last resort-take to mechanic.

1 Reply

RACEFAN966

MECHANIC
5,029 POSTS

OK if it will run when you spray juice in the intake then it isn't a ground problem. I would check the injectors. You said there are getting power but are they getting a pulse signal? To check this you will need a noid light then you plug it in to the injector harness and turn it over and see what the light does. Get back to me via pm (person message) refresh me of the problem and what you found. I must ask did you use the sensors from the mustang IE the camshaft and crankshaft and such. Some of the sensors may be different in how they function and this would keep it from starting too.