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Discussion Starter · #1 ·
96 WS6 m6 383
Alright, so after going over the entire fuel and ignition system, got my car started finally!! What a relief!.........

New problem.
I started the car, "woohoo it started!"
Went to leave about a half hour later, check engine light comes on and everything sounds "off."
Got a scanner, ran a p0336 crank sensor code, alright easy enough.
Changed the crank sensor, started it up, everything was great, no check engine light and everything sounded fine. After i shut it down and went inside for a few minutes, started it up to leave again and the same code came back and everything sounds rough again..... :craz28::craz28:

Checked the reluctor ring for movement/debris and found nothing.

So did some more checking and found that some of the wires that go to the crank sensor were resting on the exhaust and were a bit cooked, great... so today i'll be replacing those and the plug that goes to the crank sensor.


Now, if that doesn't fix it for some reason, what's next?
I was thinking about trying suicide out but we'll see lol.
pcm?
 

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just putting this out here ive been in about the same shoes before with my jeep, however jeeps CPS doesn't throw a code. but everything lead back to the CPS so i replaced it, still same problems, so i traced wires make sure everything was good, checked plugs wires/ coil, checked fuel pressure, checked volts going to each injector, check just about everything under the sun, so i took off the "New" (Never Ever Worked) CPS brought it back, got a new one and WHAM! problem fixed

basically don't rule out that it would just be a Never Ever Worked CPS

on same note im not sure if these work the same, as the jeeps, everything else seems to be different.
on a cherokee it's just basically a magnetic pick up that bolts onto the back of the bell housing and reads teeth on the fly wheel
 

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Whistles go Whoooooooooo
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fyi, the crank sensor on an LT1 does nothing useful -- it is for OBD-II misfire detection only, and is never used for position reference for spark/fuel calculations.

everything is done with the cam sensor in the back of the distributor, and it compares with the crank sensor to detect possible misfires.

you could drive the car with it unplugged and all you'll get is a check engine light.
 

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The coil, icm and cps are all on the same power circuit. Fuse 11 of under hood fuse box. If changing bad wiring doesn't pan out and stop code, check wiring of icm and coil also.
 

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Discussion Starter · #6 ·
Alright, changed the pigtail, doing the same thing.

Start it up, runs great and idles fine.
Turn it off and wait about 5-10 minutes and then start it up again and the idle is super rough and the check engine light is back on immediately.

Will check the fuse in a minute and see if there is a problem there... Should also mention i replaced the opti last week, could it be bad already?.. might be answering my own question there lol.

The thing that gets me is, why would it run normally and perfect until i shut it off and start it again? pcm getting more readings after the 2nd start up?
 

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If this was the past, I'd say you have a case of vapor lock, but those days are over.

Hopefully, your scanner does real time sensor data, if so, I would run a sensor scan on the first start up. Then shut car down, let it sit a while, and do another running sensor scan. Compare the 2 sets of readings, looking for data that has radically changed between the 2 scans. Might help give you a direction to go in.

If your scanner only reads codes, you can download the free obd2 scan program in the 4th gen section and use it to do the running sensor scan. However, you will need a cable to hook car's dlc to usb port of laptop, notebook, or desktop pc. Ebay and Amazon have elm327 cables for sale, all the time.
 

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Discussion Starter · #9 ·
ummm... i think it was a richporter tech? sounds familiar anyway. It was the only one any friggin auto stores had in my area and it had a lifetime warranty so what the hell, if it's bad i'll go get another one for free i suppose.. ugh. it was either the richporter or a re-manufactured one. pass on the re-manufactured lol



Sadly the scanner i have only reads codes,
There is an auto shop down the road from me, they have one of those uber "genesis," super computer things.. i was thinking of just paying them the cash and having them tell me what's wrong with it since i assume that computer will pinpoint it immediately.
 
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