Problem with a 1996 GMC Jimmy.?

casey

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Ok so I am by far no mechanic, and I am having problems with my Jimmy. It won't start. It was grinding like the starter was going out, so I replaced it. I've put a new fuel filter on it and it still will not start. It seems to be getting fuel, and is turning over and trying to crank but it just won't fire off. I am thinking it might be the fuel pump or a problem with the injectors. Can anyone help with any suggestions on what it could be or what to do?
 
You may be weak on fuel pressure . even a couple of lbs low on a cold start will cause a no start.
Double check cold start cranking fuel pressure. If under 63-62 lbs you have problems.
one test is to give it a squirt of carb cleaner not starting fluid. If it starts then you have a fuel pressure problem.
Run the full fuel pressure test and post back pressures.
Here is the guide lines on testing.
Hard to start cold.
Check cold start fuel pressure.
Check engine running fuel pressure.
Check engine running on the road fuel pressure.
Then shut it off and watch for fast leak down.
Pinch off at rubber part or block off return line and check full pressure.
Later V6 and V8 gm engines should have 60-66 fuel pressure.
Cold start should be 64-65 lbs of pressure.
If you do not have full fuel pressure on a cold start the injectors will not squirt fuel.
Do not leave home without it.
Engine running should be 60-66 lbs pressure depending on engine load.
Full pressure with return pinched off should be 75-85 or more.
And if it has a fast leak down after shut off you have a leak.

The 75-85 is only a check on the capable full pressure of fuel pump.
If you can not find the rubber return line check full pressure by plugging return line or just or the true full pressure can be taken direct at the end fuel filter.
What are the pressure readings that you have done.
What are your cold start pressure readings?
Post back what you have.

If the fuel pressure is good then check or replace the (ICM) But before all this check the fuse box for any bad fuse like the ECM fuse.
 


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