Jeep wont start

[cobra56889]

I have a 92 jeep wrangler that wont start it cranks like mad but seems to have no fire to the coil. I started by replacing the crank sensor then a new rotor then a new ECM i have checked all my relays and fuses and they all appear to be ok. hooked up a diagnostic computer to it and it wouldnt even connect with it. That is when i replaced my ECM. but still wont start. This all started when i removed my battery from my jeep with it running and as soon as i removed the ground it died out. So iam pretty sure the alternator is out but it should still start and run off the battery correct?? Any help would be well appreciated.

[rockreligious]

check to see if your getting fuel to (pump running?) if not then it is likely a comp problem, possibly new crank sensor if faulty(which happens) possible auto shut down relay, cam sensor in distributor or just weak battery.. I believe you have to have certain amount of voltage or computer doesnt kick on even if engine is turning.

[cobra56889]

There is fuel to the TB but no spark to the coil and the battery starts my diesel just fine so iam sure there is plenty of voltage at the battery. I got a new pickup for the distributer but i dont know how to get the distributor apart to get to the pickup. Do i have to pull the distributer out or what??

[TwistedTJTank]

My throttle position sensor (TPS) went bad and caused the same symptoms. It was a bitch because it wouldn't just 'die'. It would work then fail then work then fail. Finally got it throw an error code (check engine). Cheap fix. I think it was about $20 at Autozone and took very few minutes to swap out. Try a search on TPS*

[cobra56889]

Anymore thoughts on this I checked for fuel pressure and now i have ZERO but i still have NO SPARK GETTING TO THE COIL. HELP!!!!!!!! From what I have read the tps would not keep it from starting but instead would make it idle really high. Also tried spraying berrymans B-12 in the TB and it still would not fire so iam out of ideas maybe its time to replace with a 4.3 vortec. But would ruther just run it as is for awhile before I do that.

[yj-mule]

Well sounds like you need to check it from end to end, which is a pita.
Four quick things to check: (I ran into these)

1. No engine ground after engine swap.(started but had issues, added ground to block all was good.)
2. Busted gear on the bottom of the distributor. Take off the cap and crank over the motor. If the rotor is not turning its probably a busted distributor. It could be a busted oil pump/cam gear issue. Pull the distributor and see if the gear spins by hand without issues and turns the rotor. If the gear spins on the shaft, hold the rotor when spinning the gear, then that is bad. Pay attention to where your rotor is pointing when you remove it! You will jack your timing and really have issues unless you know how to reset it.
3. Bad coil. Self explainatory, replace the coil and see what happens.
4. Check the wiring to the coil from end to end. Replace anything splayed, frayed, or pinched.

My redneck way of checking the ignition:
Pull the cap and crank over the motor, if the rotor is turning (good), I would check the cap and rotor for good contacts. If they are good suspect the coil. The last thing is pull 1 plug, replug it into the wire and crank the motor over, see if the spark plug fires. Be carefull when doing this, if you get zapped it will hurt!

[geberhard]

Just had a similar issue and the problem was the wire and plug to the coil (this was on a 4 banger). Ask someone to try cranking it on while you shake the coil plug and wire a bit. Could be just that Alos like it was mentioned, check your battery terminals and ground, mine were corroded and after I replaced mad e ahuge difference!

Good luck!

[1987yjizzle]

you might have had a voltage spike that fried everything, cause diconnecting the battery when runnng on a fuel infected car is not the smartest thing too do

[Tammey]

What happens when you do that? I don't think it's my issue with my 87 but done so much during and after the rebuilt I have lost track of what all I did or did not do.Do you mean fry all sensors including the PCU?

[TwistedTJTank]

TPS has a 'safety' built in to prevent you from cranking it with the throttle wide open. If it thinks the hammer is down, it won't let the thing crank. That is what it was doing to mine. Turn over and over, no problem. Just couldn't get a rumble outa the exhaust.

[itisme]

I dont know if you are meaning that there is no volts going to the coil but to check of there is no volts going to the coil just unplug the plug going into the coil and connect a test light to the plug and then crank the motor with someone watching the light. If the light turns on and off then you have power going to the coil. If the light only turns on then something is bad (cant remember what though). If the light does not turn on then you have something else wrong (not sure what either). You have to have the alternating voltage to make the coil work. Two days ago i went to a resturant to eat. When i was leaving my jeep would not start. Turned out it was the coil with this test. Not sure if this is will help but it is just a thought.

[Yota Tony]

I'm gonna say the plug to coil too.
I had that problem, wiggle it a bit and it should fire right up.