92 XJ blowing F15 fuse

I have a 92 XJ with the 4.0 and automatic. Friend was driving it for a week and it left him stranded. Had 12 volts to the coil but no spark. Found F15 (engine control 1) fuse blown. Replaced fuse after disconnecting electric fan thinking it was shorting. Started right up and ran for 15 minutes no problems. Started and ran several times to see if it would quit again. Brought it to operating temp each time. All was good and took off to my aunt house. Made it to 3rd stop sign waiting for opening in traffic. Approximately 1 mile. Pulled out 5 feet and it died. Same fuse blown. Im trying to track this short down but its a wiring nightmare to me. Anyone have this same intermittant short or any good ideas other than trial and error at 3.50 a fuse and a tow bill home to find this? A burned wire or rubbed one would be fairly easy to find. Unfortunately Im not seeing either of them. Ive started going through the wiring harness looking. Distribution center is in good shape with nothing touching to cause this that i can find.

Wiggleworm said:

I have a 92 XJ with the 4.0 and automatic. Friend was driving it for a week and it left him stranded. Had 12 volts to the coil but no spark. Found F15 (engine control 1) fuse blown. Replaced fuse after disconnecting electric fan thinking it was shorting. Started right up and ran for 15 minutes no problems. Started and ran several times to see if it would quit again. Brought it to operating temp each time. All was good and took off to my aunt house. Made it to 3rd stop sign waiting for opening in traffic. Approximately 1 mile. Pulled out 5 feet and it died. Same fuse blown. Im trying to track this short down but its a wiring nightmare to me. Anyone have this same intermittant short or any good ideas other than trial and error at 3.50 a fuse and a tow bill home to find this? A burned wire or rubbed one would be fairly easy to find. Unfortunately Im not seeing either of them. Ive started going through the wiring harness looking. Distribution center is in good shape with nothing touching to cause this that i can find.

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Our 91 xj had a short the would blow one of the big main fuses in the engine bay fuse box, the engine kept running but the alternator wasn't charing eventually the car would die when the battery ran out of juice. I'd replace the fuse and it'd work fine for a few minutes then take test drive it'd blow. Once or twice I'd do it idling.

Turned out the when the shop pulled the battery cables the positive side was cheap aftermarket all the wires going to it (including the main power for the fuse box) were under a clamp, something came loose when the shop pulled the power so do something. Nothing looked different to the naked eye that I could notice.

From the way you describe it your jeep has a different fuse blowing, probably a different problem, but you might check the power source for the engine bay fuse box just to be sure it looks OK.

I'll looks around and see if there is anything I can come across that seems similar.

It appears to be a common problem a lot of threads on this;
A few ideas:
wires leading to the oxygen sensor
oxygen sensor
Wire going to the fuel pump
ignition switch

Checking the wires going in to the box to be sure no rodents have made a nest under there.

Green Mesa XJ said:

It appears to be a common problem a lot of threads on this;
A few ideas:
wires leading to the oxygen sensor
oxygen sensor
Wire going to the fuel pump
ignition switch

Checking the wires going in to the box to be sure no rodents have made a nest under there.

Click to expand...

Slide under your jeep and see if the rear o2 sensor wire came loose and is dragging on the driveshaft.

Soon as I get a little time to get back on it ill see what I can find. Definitely need to clean battery cables and one looks like it needs to be replaced. Figured out a way around blowing fuses. Auto resetting breaker soldered to blown fuse. After it shorts out Ill have to wait a few minutes and it wil have spark again and should start up and drive. Also purchased an ignition starter switch in case I need it. It has 230,000 miles so im sure its seen better days. Thanks for the quick replies and ideas.

I looked at all the suggested places for wires rubbing and grounding out without finding anything obvious. No rubbed places or anything touching on O2 sensor or fuel pump wiring. Ignition switch doesnt have any melted areas on wire connector or any areas that look like they have been shorting out. I cleaned the posts on the battery and the clamps. The wires are doubled up going to positive side for starter and distribution center. They were also kinda dirty so took them out of the clamp and used solder flux and heat to clean them a bit. Liquid flux would work better. After soldering two wires to a blown fuse and then connecting them to an auto resetting breaker i put it in and drove around the neighborhood. No dying. Getting brave and went on a 2.5 mile drive without any problems. Made a second round without any problems. Cleaning these things and putting dielectric grease on the connections seems to have fixed the problem. Hard to believe thats what caused the fuses to blow. Leaving breaker in distribution center for a while until Im sure that was it.
Id like to find a battery that has top and side connections so I could run one wire to each place. Summit has them but at 200 bucks its a little steep for me.
Green Mesa XJ and Sidewaysstarion, I appreciate all your input in trying to help me track this down.