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Jeep Cranks, Won't Really Start

756 Views 10 Replies 5 Participants Last post by  CP30
To start this off I was going on a trip and leaving the jeep behind, I was looking under the hood for some reason and left it open. It rained that night and it was shut the next day.

Apparently the light bar was on for quite awhile, I traced it to the relay getting waterlogged and shorting out, this fried the relay but the rest is good, the light bar is connected to the battery terminals, just including this in case it could've messed something up.

So! After I got back a few days later it started up fine, on the way to a friends house it stalled out, I stopped and it started right back up. Since it started back up I figured it was water in a connection and would evaporate out. Stupid I know. On the way back it got worse, the jeep kept stalling sometimes right after start, but mostly at idle speed or when I gave it more gas. It stayed running fine when I just kept it at a consistent speed. After one of the shut down start up cycles it threw a code for the camshaft position sensor being disconnected, but it went away on the next shut down start up.

The next day I tried starting it again, but it wouldn't turn over, it cranks fine though. I cleaned up the battery connections as well as blasted the fuse box, the camshaft position sensor connection, the oil pressure sensor connection, the three harness connections on the passenger firewall next to the engine, the three connections that plug into what I think is the PCM (the box on the driver side fender), and the coil rail connection.

I also tried replacing the camshaft position sensor, that didn't help. I believe I checked the crankshaft position sensor, but it's connection seems to be in a different place than I keep finding online. The sensor is at the 1 o'clock position looking from the front and the connection is at around 3 and behind it attached to a bracket on the transmission. I tested pins B and C on that connection and got a reading of around 60 M ohms, which I believe is higher than the proper testing range.

One more weird happening is after cranking it some times the oil pressure gauge jumps to above 80, but goes back to just above 0 after I turn the jeep off then on again.

Any help is appreciated and I can upload some photos if need be.
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I just went through a similar exercise after replacing and injector on my '99. The injector #3 wire was caught against the throttle cable support bracket. Engine was running great and then instantly stopped when I moved it. Kept cranking and would not start. I sprayed some starter spray into the throttle body and nothing. I checked all the injector and sensor connectors and tried cranking a few more times, still nothing. I had taken the fuel rail off to replace the injector so I pressed the valve and fuel sprayed out. Checked that a few times and definitely looked like I had fuel pressure. Next was spark. Removed a spark plug and then put the wire and plug by the block while I had someone crank the engine. No spark. I checked the CPS and saw infinite resistance between terminal b and c. After all that cranking, the check engine light finally came on. I forget the code, but the description was auto shut down circuit had no voltage. I did some googling and checked the ASD relay by swapping. Still no go. Did some more searching and found there is a 20 amp fuse in the engine fuse box. That fuse is triggered by ignition components including the injectors. I was looking for which fuse # it was and of course can't find it right now. It's a 20 amp fuse and was blown. I replaced that and it fired right up. My guess is when I moved the injector, it shorted against the bracket and blew the fuse.

Point of the story. check fuel and spark. It has to be one or the other missing.
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