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LSXmyford · #7 (**permalink**) 08-21-2008, 01:44 PM

Quote:

Originally Posted by NITROUS

Turn ON the ignition, with the engine OFF.
Disconnect the CKP sensor.
Measure the voltage from the CKP sensor 12 volt reference circuit and a good ground.
Compare the measured voltage with the system voltage.
Is the difference more than 0.5V?
If not replace the CKP.
If yes, test for a short to ground in the CKP 12 volt reference circuit or the CMP sensor 12 volt reference circuit.
Test for poor connections at the coils.
If problem isn't solved there has to be a ground issue somewhere or check fuses again.
Check and clear all DTC's and scan again.

I'd start here and rule out the CKP and CMP.

Voltage from cam sensor = 11.49
voltage at crank = 11.48
voltage at pcm 12v constant (system voltage?) = 12.4

something of note, when he put the meter probe to the crank sensor reference circuit, it shown 11.48, when he removed his probe from ground, it would show 6 volts...WTH?

another puzzler. he tested the ckp wires from pigtail to pcm, and resistance was correct, nothing out of the ordinary.

all coil connections have been removed and reconnected. he even tested resistance from the coil to the pcm, all checked out good.

no codes.

any suggestions.

Quote:

Low reference
Chassis ground
Ignition 1 voltage
The appropriate IC circuit

what should be seen voltage wise at each of these? he has 11.4, I would assume at the ignition voltage, and he has one proven ground, what about the IC circuit, while cranking and low reference?