I bought a 98 zj a couple days ago. Tonight driving it about 35 miles it bucked a couple times down the highway like it had a random miss did this about 4 times we went into restaurant for about 90 mins when we came out to leave and the Jeep just cranked. I listened for the fuel pump and could hear it prime so I pulled coil wire and when we cranked it the coil had no spark. So I put it back on and then it fired up and ran about 10 seconds and died. So I checked codes with my scanner and nothing so we started it ago and this time it kept running for ten minutes without an issue as it was running I wiggled wiring at the pcm and the coil no effect . So we decided to drive it home well it made it home no issues since. When I was wiggling the pcm wires. I decided to swap the asd relay and like I said it hasn't missed a beat since. But I'm skeptical that was it. What else should I check? There's are no codes. Temp doesn't seem to effect it and when it did for it was like someone just turned it off no coughing or hiccup. Just all the sudden off. I'm lost please help. Thanks everyone
random crank with no spark in grand cherokee
- Thread starter ram_man
- Start date
- Status
Nick1994
$100 site donor 2024
My grandpa's 96' Jeep Cherokee with the 4.0L had this exact same thing happen 3 months ago. It was the cam position sensor under the distribut cap. The distributor shaft was wobbly (wiggle it back and forth to check for play) and it chewed up the cam sensor.
A new distributor and cam sensor fixed this but it still had a check engine light for misfire and it turns out the timing chain was stretched and needing replacement. Been perfect since.
A new distributor and cam sensor fixed this but it still had a check engine light for misfire and it turns out the timing chain was stretched and needing replacement. Been perfect since.
What engine?
I dont know that cam sensor would cause a no fuel condition. on my 92 with the 4.0 I did lose a crank sensor.... are you getting any diagnostic codes? most of the jeeps its easy to read the code: turn the key on, off, on, off, on... on the third cycle leave the ignition on and any codes should display on the odometer.
Nick1994
$100 site donor 2024
Is it loose or tight? Maybe you can disconnect it and make sure it isn't corroded, and put some dielectric grease in. Perhaps that could solve it
Pull the connector and tighten the connections. I have heard about the wiring harness rubbing on a stud in the back of the valve cover. Look there too.
On many crankshaft position sensors, when you crank the engine you can see the rpm rise on the tachometer if the crank sensor is working properly. If the crank sensor is not working properly, the tachometer gauge doesn't fluctuate at all while cranking the engine and remains at zero. Pretty standard (and easy) way to diagnose a crank position sensor or find it to be something else.
Edit: saw it was the wiring. Jeeps are notorious for having wiring gremlins, Good luck with that.
Edit: saw it was the wiring. Jeeps are notorious for having wiring gremlins, Good luck with that.
I recently had a problem with windows not working. They were intermittent for a while and then quit working altogether. Got pretty good at taking off door panels and checking and changing master switch. Nothing helped. Then I finally cut the rubber that covers harness as it comes out of the jeep body and goes into the door. Several wires had broken due to repetitive motion. Took an hour of soldering to repair and wrap and tie wrap my rubber over the harness.
Now I worry about othe wires in the Jeep. She is 21 years old and I bet other copper wires are waiting to do the same.
Now I worry about othe wires in the Jeep. She is 21 years old and I bet other copper wires are waiting to do the same.
Originally Posted By: ram_man
How do you tighten the connections?
Bend the pins or squeeze the female connectors so they fit tighter.
How do you tighten the connections?
Bend the pins or squeeze the female connectors so they fit tighter.
- Status
