Out of gas, so the truck says..
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Joined: Apr 2010
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From: Clayton MI
If it starts and runs for a bit, you probably have a bad relay control circuit somewhere. Scan tool should give you any codes, and that will be a place to start. Might be ignition switch, failing sensor, or just a bad ground somewhere.
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Joined: May 2008
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From: NH
Ok, I have cleaned the fuses, PCM itself, all connections and grounds to it itself.. I have also removed the big plug in the front fuse box under the hood with the screw? Cleaned it, and put it back.. I wiggled the plugs into the PCM, before cleaning, and my guages worked again.. Truck started but only ran a few seconds and died, three times.. Now Im back to nothing, no guages, no starting.. I've pulled everything out of under the dash, havent got to check those wires yet. If the PCM is fried, will it start like that, and then stop again? Im borrowing a scan tool this week
Ok.. I checked the wires, they are fine.. wiggled again, nothing. Check this out. I hooked up a scan tool to it.. No codes.. It says it is connected, Nothing is stored on the computer. When I turn it ON not start, my guages dont work. When I plug in the scanner, Guages come on.. TRUCK STARTS.. If I pull the scanner out, it dies immediately. Now, when I have it plugged in and the truck running, all guages work, except the oil pressure!! Is there something I knocked loose the senses oil pressure, that would stop the truck from running!? I have never seen this before.
Some research is telling me my scan tool is providing a ground for my pcm.. Still dunno why my oil pressure is dead, or if it really is dead, or maybe its the cause? Going to check my grounds now.
Amateur
Joined: Jun 2012
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Yup, its almost certainly a ground issue. There are grounds everywhere on the truck. Check ones that don't even seem related. If you can't find anything, run a ground strap from the PCM to the body and to the frame.
Travis
Travis
Got it!! I changed the PS Pump a few months back, and was in a major hurry, Husband was taken via ambulance to the hospital.. In my panic I broke the grounds from the battery to the ground by the pump, and from there another one to the PCM.. Well, my wire came loose. I rewired it, and it runs great now!! All this over a silly wire? At least I didnt have to fork out 200-600 bucks! Thanks a bunch guys!