91 f350 5.8 4x4 no start PLEASE HELP!
#1
91 f350 5.8 4x4 no start PLEASE HELP!
I bought someone else's problem. He gave up on it, tired of spending money and time on and in it! It was a plow truck. Started running bad and just got worse as time went on.
When I bought it it would only start w/ starting fluid and then would continue to run but poorly. It sat for two years until I recently got to it.
So here's where i'm at with it. It has spark at the plugs, I verified ignition timing/ distributor installation, fuel pressure 40psi key-on, good compression 120psi on all cylinders. I have 12volts to the injectors but I DO NOT HAVE INJECTOR PULSE! I verified the grounds and powers at the ecm. I also have a 5 volt reference at the tps and the single wire connector at the dlc. THE CHECK ENGINE LIGHT NEVER LIGHTS UP AND NO SCANNER COMMUNICATION! (I checked the scanner on my 92 f350 and no problem)
I'm about to replace the ecm. Any ideas?
When I bought it it would only start w/ starting fluid and then would continue to run but poorly. It sat for two years until I recently got to it.
So here's where i'm at with it. It has spark at the plugs, I verified ignition timing/ distributor installation, fuel pressure 40psi key-on, good compression 120psi on all cylinders. I have 12volts to the injectors but I DO NOT HAVE INJECTOR PULSE! I verified the grounds and powers at the ecm. I also have a 5 volt reference at the tps and the single wire connector at the dlc. THE CHECK ENGINE LIGHT NEVER LIGHTS UP AND NO SCANNER COMMUNICATION! (I checked the scanner on my 92 f350 and no problem)
I'm about to replace the ecm. Any ideas?
#2
I did a 5.8 swap on my '90 and had a lot of grief with the running. I was using an ECM from an '89 w/ a C-6 (I've got the 5 spd) and it ran generally crappy and cut out a lot. I replaced the ECM and it runs way better. I don't know what your problem is from the information given but if you do decide to replace the ECM, I got mine from Amazon. It ran me $170 and the best thing is no core charge. The C-6 is different from the MT and not having the same one to turn in would have cost me an additional $80. A scanner didn't work on mine either and neither did an analog VOM. I ran the jumper for the dash light and am able to retrieve codes that way.
#3
Classic symptoms of a failed PCM. As a precaution I would make sure the CEL bulb is good and take a few minutes to clean the contact on the data link then try the code reader again. If the issue remains then you most likely have a bad PCM.
#5
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