wingnut37

Gentlemen, the plot thickens. After replacing the distributor, I now have spark, but still won't fire. I am positive I indexed it correctly -- I suppose anything can happen, but when all was said and done, the rotor was dead on my index mark. Suspecting now that I've had two separate issues, which with some bad luck, happened at the same time.

I've cracked open the old distributor (the sync sensor was under a plastic plate) -- not much to it, looks like a little pickup, not sure if there is a way to test it or not. Out of curiosity, I tested the TPS, and got voltage readings within specs.

The more I'm thinking about this, when I took off the cap, there was a fair amount of carbon deposit on each terminal (cleaned up now). Maybe I've now got spark arcing through the cap and not getting to the right cylinder? Yuck...

Rocks, Popeye, wish I could help you --- I might not be the guy with the answers, but you found the right place when you found cherokeeforum.

rockswealth

Thanks Guys, Wingnut You are right about the forum, I have learned a lot already and am checking every suggestion I can without my mechanic around. They are the best.

You are however doing better then me, at least you get a spark. LOL

wingnut37

Ok, problem finally diagnosed. Two problems actually. One was a bad sync sensor. After that, I had spark, but the thing still wouldn't run. I'd started another thread relating to it, where I'd thought I'd mis-indexed the distributor, and was going about finding TDC to reindex it. With plug #1 pulled (for compression tester), I bumped the engine to get close to TDC, and it ran, with the plug out. The rest of the explanation is from the other thread....

Well, I think I've stumbled upon an answer, albeit in a roundabout way. I started to make a video to post to prove I wasn't crazy. By pure coincidence, every time I attempted to start the jeep with the #1 plug installed, I was inside the vehicle, using the ignition. Each time I started it with the plug out, I started it using jumper wires on the solenoid. As I went to start it this time, I put all plugs in, and used the jumper wires. Started and ran beautifully. ITS THE IGNITION SWITCH. I suspect that if anyone else tries it, their jeep too will run with a plug pulled, and with a little dumb luck, could also smother the engine by pressing a compression gauge in at just the wrong time. I've done it 10 times now, and each time it starts and runs with the jumper wires, but will not start and run by putting the key into the start position. Cranks, but does not fire. Can't explain why, perhaps that's just how ignition switches fail?? Either way, I'm going to get a beer. Thoughts? And many thanks to those who've taken the time to help.

glennwilfong

Waa the key in the off position im having a problem after a fire by battery repaired all wiring i hope and to fuel pump relay my fuel pump works when bypassed but no start no spark thanks

wingnut37

Glenn, no, in my case, the key still needs to be in the run position in order to energize the circuitry to ECU, etc. My recent experience says spark problems are due to CPS, sync sensor in the distributor, ignition coil or wiring. Given that you had a fire, I'd go after wiring and start backprobing for continuity... more details you can give, the more people can help you out... best of luck.

glennwilfong

Thanks wingnut37

rrich

Another made up story like your previous thread?

"Runs on 5 cylinders, but not 6!"

The ignition switch is NOT cylinder specific!

We thought you had a legitimate problem. You do, but not with a Jeep.

wingnut37

RRich. Allow me to be more clear: The piece of information I'd not realized to be critical at the time was that when attempting to start the jeep, I'd been using two separate circuits. One was the ignition switch turned to the start position. The other was using key-in-run position, and jumper wires to the starter solenoid. After figuring that out, I could ascertain that the problem must be in the ignition switch. The fact that it would run on 5 but not 6 was correct, but lacked the additional piece of data -- using two separate circuits to start the vehicle. Of course the ignition switch is not cylinder specific.

I did my best to describe the problems thoroughly and accurately. My apologies for any confusion introduced, it was purely incidental -- I can assure you that I was just as confused. As for your accusation of my making things up, I can also assure you that I have better things to do with my time. Again, apologies for confusion, and apologies for unleashing your inner *****, RRich.

Thanks to all who tried to help, without being self-righteous.

rockswealth

Okay today I had my mechanic check all the grounding wires and he says they look fine. However we did find a problem the 30a fuse under the hood was blown. I got excited for a minute thinking I was going to get my Jeep back on the road. No such luck. Put a new one in and blew it without starting. Does this mean I have a short some where and where would be the most logical place to look? Thanks guys

Rocks

ejxj96

Check the wires to you o2 sensors, mine melted where they passed by the exhaust and shorted blowing the 30 amp fuse going to the asd relay.

rockswealth

Thanks ejxj96,

Well some how not sure how, she is running again. Woo Hoo. We cleaned all the ground connections, then replaced the 30a that keep busting, took off one of the plug wires and put plug in, turned all the lights off, to check for spark and wallah she started and did not blow the fuse. I am so excited to have her back on the road.

Thank you all for your input. You are the best.

freegdr

still check o2 wiring at rear sensor very common issue . one question for every one why has no one checkeed for codes even if lights not on codes can be stored the diagnostic system is there for aa reason can cave a lot of money throwing parts at vechicles .

popeye13433

Hey i checked codes the only thing i had was battery disconnected and O2 sensor but my CEL was not on. in the jeep can the O2 sensor cause a no spark issue?

Rita

Started my jeep up, drove about 100 yards or so and it shut off and would not start back up. Cranks but won't start. In reading all the jeep forums, I have changed the crankshaft sensor, cam shaft sensor and the ecm. Still same thing cranks but won't start. Also I have checked for spark at coil and no spark, my fuel pump isn't coming on either when I turn the key on. Not sure what I should check next any help is greatly appreciated