Help! Short log included.

[kistlerjm9]

So I was driving along and the maro just shut off. Great fuel pressure, no spark or injector pulse. Was able to flash computer, grounds all look good. So I went out to mess around with her again and she fired right up. So I logged a little bit a data and she died. Wont start again. Im thinking bad crank sensor, but if you can look at the log and see if you see anything at all. Im lost.

[joecar]

While cranking can you read RPM...?

If not, then there's no crank sensor signal (failure in the senor or the wiring to it).

Ignition and injector signals are timed from the crank sensor signal.

[kistlerjm9]

yep not able to read rpms while cranking... have voltage to the sensor, will replace in the morning and post back thanks. wasnt sure if the crank sensor control injector signal as well.

[joecar]

If you have a DMM you should see about 1 to 2 volts AC while cranking.

[kistlerjm9]

Got voltage to all 3 wires? 11.5 to the green, .4v to yellow and black and .2v to the blue. I thought one of those was a ground. I replaced the ckp sensor and same thing will run few a minutes and just shut off, no codes. Communication to the computer is still good but that is the only thing that can still be wrong. I wired the reverse lock out to the correct pin and used a diode. wonder if i still got a surge and fried the comp. Thats the only thing I touched on the computer and it works properly. IDK im about ready to burn this bitch to the ground.

[joecar]

I assume you took all measurements wrt engine ground (and while cranking)...?


dk blu/wht = signal -> 0.2V is too low (did you select V AC on the DMM)...?

lt grn = voltage reference (thru PCM) -> 11.5V is ok.

yel/bla = ground reference (thru PCM) -> 0.4V is maybe ok.

See attached wire diagram.

[kistlerjm9]

yeah those were all while cranking and for the signal sorry i get 1.2v, but i scanned again today while it wouldnt start and i get no voltage anywhere while cranking.no rpm's, no o2 voltage ect, only reading that works is throttle position and map.

[kistlerjm9]

i think the pcm is losing ground internally hence the reason for the intermitant starting. next tool, blow torch anyone.

[kistlerjm9]

well after cranking it for forever i got it to kick the code p0335 dont understand its a brand new sensor and the wiring seems fine?

[joecar]

See attached procedure.

Are you sure the wiring is fine (don't assume)...

And new sensors have been known to be bad.

Cheers,
Joe