It sounds like something is a miss with the security system. Usually will cause a momentary start, then a shut down. The BCM sends a status signal to the PCM and there is no way to fool it. Try locking and unlocking the passenger door with a key.
Sounds like what you are describing at the coil is a loss of the signal from PCM. My advise is to check the crank sensor with a meter.
Does the CEL come on for 3 seconds when the ingnition switch is placed in the ON position?
Agree on checking the crank sensor with a multimeter on the disconnected female connector/plug to the sensor itself. With the meter set to one of the lowest ohm settings, and locking tab on the connector up, make sure you place the black probe on the middle B pin (ground cavity) and red probe on the right C pin (power). The reading should be "open", same as if the probes weren't touching anything, and any resistance at all indicates you have a bad crank sensor.
When completing this test you may also want to move the crank sensor connector from the passenger side to the drivers side to see if the readings change. On one of my bad crank sensors the reading on the passenger side was good but on the driver's side it read bad with resistance. Turned out the wires which make a sharp turn coming out of the crank sensor itself must have been shorted together.
As already mentioned aftermarket crank sensors are a crap-shoot and only go with Mopar sensors. I learned this harsh lesson with 2 new aftermarket crank sensors which drove me nuts since they only cured my stall/no-start problems part of the time. Once I went to a Mopar crank sensor my problems were resolved. Not saying this is your particular problem, since the electronics on these ZJ's are so complicated, but the test is worth a try. Good luck!
Yeah zeejay I tried that still nothing n yes the cel comes on, before I replaced the pcm is wasn't coming on. Blurb ill try that, I just need to find where I can borrow one. I don't have money to go out n buy one of thos thank you guys alot.
Those multmeters are a lot less expensive than you may think Tttruim and eventually you're going to need one to troubleshoot electrical issues/problems on your ZJ. Walmart sells some for $12-$15 and I paid $20-$25 for the below GB one at my local hardware. Comes in real handy for testing continuity/AC current around the house in addition to continuity/DC current on my Jeeps.
Walmart also sells a set of red/black jumper wires with alligator clips for attaching the probes to connectors/grounds for $3. Would suggest buying a set since they come in real handy in using with a meter.
We can help guide you how to use one and there's plenty of youtube videos out there if you do a search. Good luck.
"Walmart also sells a set of red/black jumper wires with alligator clips for attaching the probes to connectors/grounds for $3. Would suggest buying a set since they come in real handy in using with a meter."
If you own a ZJ, you WILL use these eventually. Best money I ever spent.
Got a crankshaft sensor from the dealer, replaced it n still no start. had it on the jumper cables because the battery was dead, turnt key over just cranking, no start n then the check engine light came on its putting out code 54 now, so something to do with the cam sensor. -_- n now the vic is saying check battery! one problem after another.......
There's no spark, fuel pressure is fine. When I tested the coil there was no power coming out of the coil but there was power coming to it. But the coil is perfect. I don't know I'm thinking towards the bcm now since the alarm doesn't work no more. When it used too.
I had a friend with a scanner tool come over n plug it in n what not was just telling me the **** I already know, n I was just thinking to myself well duh moron every time you get done messing around you unhook the battery so nothing is never gonna pop up, so just now I threw it on the jumper cables n sat there for about 20 mins with the key on the on position n I start getting more cel code. So there's some idk descent news I guess hahaha it's telling me on the dash 12, 42, 22, 24, 23, 55. I've always just getting 12, 55 I know thos are the okay ones lol
22 Engine coolant temperature sensor above or below acceptable voltage. 23 Intake air temperature sensor input above or below acceptable voltage. 24 Throttle position sensor input above or below acceptable voltage. TPS signal does not correlate to MAP sensor.
An open or shorted condition detected in the auto shutdown relay circuit. An open condition detected in the ASD relay output circuit. An open or shorted condition detected in the fuel pump relay control circuit. An open circuit between PCM and fuel gauge sending unit. Circuit shorted to voltage between PCM and fuel gauge sending unit. No movement of fuel level sender detected.