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Idahome
Joined: Wed May 2nd, 2018
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I would simply unhook pcm wiring connnector, check continuity to ground from each of the injector wires ground wires.....see if one beeps = you found your short to ground.
Each injector has a ground wire goes directly from injector to PCM........so none of them should have continuity to ground
My $5 is on a bad/aging PCM after the wiring checks out.... I would open the PCM and have a look at the internal circuits/capacitors
In 25 years I replaced like 3-4 PCM's total! And most of those were due to user error, not unhooking the battery while welding, etc
But in the last 3 years I have seen 5-6 PCMs go bad in Gen I trucks (91-94 explorer) so these PCM's are just getting older and the weak ones are failing. Afterall half of the eec-iv PCMs function is like a big power relay, they wear out in time.........plus mounted in the drivers kick panel, they get exposed to leaky windshields, mildew/wet interiors, etc........
USUALLY When more then one injector is stuck open and you tell me 1994 I say you smell your computer, does it smell like electrical burnt smoke??? if it does tell tale sign of bad PCM
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I build custom RBV, specializing in drivetrain conversions, wiring, suspension and complete custom trucks