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Yj with electrical problems

I have an 88 wrangler with the 4.2L six. I parked it a while back when the hydraulic clutch wasn't engaging properly. I had no time to try and bleed it, or replace it. So...time passes. Its been parked for 4-5 months and I finally have time to work on it. I went to start it, and surprise the battery was dead. Replaced the battery. Then it would crank but not fire. I checked fuel, plugs, etc. Replaced the plugs, plug wires are pretty new, no obvious problem there. carb is getting fuel okay. cranked it over again and the damn starter wont disengage. I thought perhaps all my cranking on it fried the starter. Replaced the starter. New starter does the same thing. Now i have to pull the battery cable to stop the starter once its turned over, still wont start. I checked for spark at the coil and found that I have spark when the ignition is turned over (just for a moment) and then nothing. If i tap the positive lead on the battery terminal while the engine is cranking, it tries to start. If I could tap it constantly enough then I could get it to stay running. A little inconvenient while driving down the road. The key in my ignition is loose, and has been for years, could this be the cause of the problem? I pulled off the wheel and got to the switch but I cant tell if its remaining engaged or not. I also suspected the little solenoid on the fire wall. I pulled it off and opened it up. It has no contact until the key is turned to engage it, so I assume its fine. oh...and I replaced the coil for good measure. I'm at the point where I'm about to pull the loom and look for fried wires. Has anyone had a similar experience? Any help would be greatly appreciated. Thanks much.

-cj

Reply to
Reh
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The firewall solenoid could be the cause of most of your troubles. It controls the juice to the starter and it sends power to the coil when the key is in 'start'. You already get a normal spark flash when the key goes to 'run.

The ignition switch isn't near the key. It is down at the bottom of the steering column. That really doesn't sound like it has issues.

It also sounds like you have a bad connection between the battery cable and it's battery post clamp.

Another one to check on an 88 is the wire mesh strap from the engine head to the firewall. When it goes rotten you can get ground theft and ground loop issues.

A bad alternator can also cause the starter to keep on going. You could pull the small plastic 2 wire plug on the alternator just to be sure this isn't a problem. The brown wire in this plug is the alternator's trigger wire and it connects to the coil power.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's Canadian Off Road Trips Photos: N>
Reply to
Mike Romain

Hey Mike thanks for the response. I picked up a new starter relay and that solved the problem of the starter remaining engaged. Now I just cant get a constant spark at the distributor. When the key is turned to the start position I get an initial spark, then another maybe two or three seconds later as the engine is turning over. I checked the ground strap and It looks sound, I also checked my battery connections..no problems there...could this be an ignition module problem? Anyone have a similar problem? Thanks in advance,

-Chris.

Mike Roma> The firewall solenoid could be the cause of most of your troubles. It

Reply to
Reh

You have a ballast resistor wire that feeds the coil when the key is in run. When the key is in start, you have a direct 12 volt feed from that solenoid to the coil for spark. There are 2 green wires on that solenoid. I have seen them mixed up a few times which ends up as a no start and strange spark flashes.

If you suspect no spark when cranking over, you can just add a jumper cable from the battery positive to the coil to see if it then fires up. If it does, you have a bad connection. Be aware it won't shut down with that jumper cable in place.

If the ignition module isn't getting a ground, it will not put out spark. It's ground is that mesh cable. I use booster cables and run one from the battery negative to the firewall or right to the ignition module case to test that.

The connections on the coil could need to be cleaned too. They have a 'very' poor power plug to the coil.

You 'could' have a bad ignition module, but that would be strange. If you do go for a new one, stay far far away from a Wells unit. I have seen and heard of a pile of them that come dead out of the box.

Just FYI, the Haynes CJ manual has excellent wiring diagrams and engine stuff for your 258. Way better than any YJ manual. Just use the 1986 wiring.

One other strange one I have seen is the YJ spark plugs get too wet with gas to work. The gas washes lots of carbon and crud off the heads and fouls the plugs. Might be worth a check on one of them...

Mike

Reh wrote:

Reply to
Mike Romain

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