95 YJ Starting Failure

[RobRey]

95 YJ, 2.5. Starting problem last two weeks. 1st occurance parked in the driveway after a short trip. In full Sun. Later in the day would not start, although the motor was turning as normal.
Would not start next morning. Towed to garage. Next morning started perfectly.
Same occurance two days ago. Sat in driveway after a short trip. Would not start later in the day. Cool last two nights, started perfectly this morning. HELP!

 

[jimogeek]

95 YJ, 2.5. Starting problem last two weeks. 1st occurance parked in the driveway after a short trip. In full Sun. Later in the day would not start, although the motor was turning as normal.
Would not start next morning. Towed to garage. Next morning started perfectly.
Same occurance two days ago. Sat in driveway after a short trip. Would not start later in the day. Cool last two nights, started perfectly this morning. HELP!

It's intermittent, the first thing I'd check is that your fuel pump is running. Turn the key, do you hear it humming? You could get a cheap fuel pressure tester or borrow one from Autozone/OReilly. Could be a bad pump, ground, something. If it's working, I'd look to your sensors. The crank position sensor or cam sensor in the distributor are likely culprits, pop your coil wire off from the distributor or a spark plug wire and see if you're getting spark. If the spark is intermittent it's likely one of those two sensors.

 

[dieselearl]

when was fuel filter last replaced? start checking as in a basic tune-up, dont start replacing parts to check. good luck and please keep us post, your post will help other on forum.

 

[redbullet]

Is your battery fully charged?
Checked all the grounds?

 

[Florida Black Bear]

It's intermittent, the first thing I'd check is that your fuel pump is running. Turn the key, do you hear it humming? You could get a cheap fuel pressure tester or borrow one from Autozone/OReilly. Could be a bad pump, ground, something. If it's working, I'd look to your sensors. The crank position sensor or cam sensor in the distributor are likely culprits, pop your coil wire off from the distributor or a spark plug wire and see if you're getting spark. If the spark is intermittent it's likely one of those two sensors.

I once spent a lot of time and money chasing what I thought was a vapor-lock problem (Florida heat). It ended up being a fuel filter in the Driver's side rear quarter-panel that you could hardly blow through. Try looking for that.

92 YJ with 1978 CJ7 304 V8