Turning on headlights "kills" engine... Help Please

[Michael_h359]

Short story. I turn on headlights and the engine will die, turn on turn signals and engine will die, hazards... anything electrical and it dies..


I just bought an 88 yj jeep 4.2 6 cylinder. It starts fine and idles fine no issues. Use to be able to drive it a little and it would randomly die but i could immediately restart it and continue on for a little before happening again. now when i start the car the engine will die when i turn on anything electrical. IE head lights, dashboard, hazards, step on the brake pedal " If i remove the bulbs and step on the brake the engine wont die. " wiper blades, cabin fan, turn signals anything electrical it will die. Other than that it runs good no hiccups or anything. Any help would be appreciated thanks. Have owned the jeep about 3 days now.

 

[56cj5]

Check the voltage regulator. Or the alternator ..., or even the battery. But if not any of those. Maybe you have a severe short somewhere? But I think if that where the case nothing would work. Not even the starter !

 

[jps4jeep]

Thing is, you should be able to remove the battery from a carbed motor w/o electric fuel pump and it should remain running.

Regardless

I would start with the alternator and battery, checking voltage and cable conditions as mentioned. I am leaning towards a battery cable, inside the cable if you get corrosion inside the sheething, there will be more resistance, it will cause wierd conditions, most commonly a hard start situation. other than that. dunno.

if you hit your brake lights does it also stall?
horn?
radio?

Are all the stalling conditions occuring through the headlight switch and the blnkers?

 

[Michael_h359]

I started the engine and removed the battery and car runs fine,

The horn is the only thing electrical that seems to work without killin engine though it might effect rpms a lil to small to tell.

and yes car dies when i hit my brake lights

radio does not work, installed aftermarket but does not work just says time

horn does not seem to effect engine

yes stalling continues through headlight switch and turn signals as well as turning the fan on for heating

 

[MY95YJ]

A friend had the same issue, turned out to be a bad wire coming from the alltinator....

-James

 

[Michael_h359]

What do you mean a bad wire? Not connected correctly,corrosion in wire?

Thanks james.

 

[superj]

I bet it's something is wired wrong so it's taking power from the coil when you hit those electrical accessories

 

[Michael_h359]

Just an update to what i have done so far

- Tested battery and alternator tested fine
- ran jumper from ignition to battery car still died when hitting headlights

 

[MY95YJ]

The wire had some corrosion in it by the connector. It would cause a short every time a load was put on the electrical an kill the jeep. If I remember right it was by where the wiring goes through the fire wall.

-James

 

[Michael_h359]

Thank you james i will try that in the morning,

Also update, i have took all fushes out of fuse box and car will still turn on, as well as the headlights.

And that should not happend right.....????

 

[JPNinPA]

CPS will cause random engine dieing.
Also Check all your ground wires and connections. There should be six points. Engine to tub both sides. Battery to Tub both sides and Tub to Chassis. be sure they are cleaned. Sand both area and wire. Replace any that look corroded.

 

[Michael_h359]

Am giving up on the jeep, not happy at all thinking about donating it. Anyone want an 88 jeep for cheap, i think it just needs a new wire harness.

 

[JPNinPA]

Where are you at?

 

[jps4jeep]

X2 on location, put me second in line.

 

[superj]

it should not run if you pull all the fuses. i would look for some extra home made wiring.

 

[Michael_h359]

JPNinPA, Your were right it was a ground issue or lack their of. I ran new grounds from battery to body, chasis, engine and cleaned existing ones. Fixed my issue! Thank you all for your input it was very much appreciated. Nice to know their are people out there willing to help.

Thanks again to all!

Sorry, dont want to donate the jeep anymore.... :lol:

 

[JPNinPA]

Sorry, dont want to donate the jeep anymore.... :lol:

Glad you got it fixed. Cheers!:beer: