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Picked up a 95 jeep with a 5.2 that runs really rough. Fuel pressure is good, injectors are good, injector wiring is good, TPS, IAC, and MAP test fine. Good continuity between PCM plug and all critical sensors....tonight I noticed on both the cam and crank sensor I have 8v power supply, good ground, but with both sensors unplugged I have 2-3v at the signal wire of each harness plug. Is this normal? I would think the signal wire would have 0v with the sensor unplugged but maybe I am wrong.
Fuel pressure is good, injectors are good, injector wiring is good, TPS, IAC, and MAP test fine.
Did you check what the intake manifold vacuum is at idle using a guage? If it is not between 18-21 in Hg, check the EGR valve it may be stuck partially open. This was a common failure on this vintage.
both the cam and crank sensor I have 8v power supply, good ground, but with both sensors unplugged I have 2-3v at the signal wire of each harness plug. Is this normal?
From memory, it is correct, 8 volts is normal and unplugged that was a bias voltage, all good!
Perform a cylinder contribution test, to be sure all 8 cylinders are contributing to combustion as well.
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Last edit: 1 year 11 months ago by Paul P.. Reason: added content
