What is the best way to wire up a kill switch? (30 amps) to kill power since it won't stop running. I was thinking fuel pump unless anyone has a better idea. 1987 jeep 4.0

 

I'd suggest fixing the issue correctly.

If it's not cutting off when you turn the key off I'd start looking for a short.

I had one do that before. I swapped out the ECU with a spare one I had and that fixed the issue.

 

The quick and dirty way is to add a switch to interrupt the coil on the ASD relay.
But ITA with Lowrange, fix it the right way. This may be a symptom of an underlying larger problem that will leave you stranded at some point.

 

You tie a string to the ASD relay, run it into the cab and just pull the string when you want to cut it off.

If it's shorted well enough to keep the Jeep running then I'd guess it's got power all the time. Which means your coil is not going to be happy after a while.

 

Oh heck. Tie the string to the end of the wiper blade. Wipers ON = Engine OFF.
OP is in Texas, they don't need wipers down there.

To add "antitheft", run the wipers on high and leave the string a bit loose. Watch for relay to launch...you're all set.

 

Well ive already replaced ecu, starter, starter relay, ignition switch, ignition cylinder, I heard somewhere it could be a bad alternator giving frequent charge? The last owner had it hooked up negative to starter positive to engine block, so I'm thinking it could be a shorted alternator like everything else?

 

I fixed the same problem yesterday, but it was a lawn mover.
Every time I have electrical problem I begin from electrical diagram.
All bottom fuses shouldn't have voltage. I guess, ign. switch is worn out.
1. remove key, check if fuses have voltage.
2. if they do, remove connector from ign. switch
3. if voltage disappeared, replace ignition switch.
4. if voltage is still there, begin pulling bottom fuses one by one checking voltage
5. if voltage still there with removed fuses, there is short between ign switch and fuses
6 if one of removed switches eliminated voltage, short is in circuit of that fuse.

 

If your not going to fix the real problem you can always splice at you coil. I always did that for a kill switch on all my cars. Not because it wouldn't shut off just so they wouldn't get stolen. But, I would really try to fix the problem. But, That's me.

 

Could it be the alternator? I'd love to fix the problem, but I've done everything anyone can think of...

 

87 is wired differently than the '97 pictured above. I'd start looking for relays with the contacts stuck shut or socket problems. It's about the only thing you haven't changed.
I highly doubt it's the alternator.

 

Well I've replaced all 5 relays too.

 

As much as I hate to agree with the 5carrace dude you need to start tracing circuits.

 

Sweet. Well first I'm gunna pull the alternator and get it bench tested. People say if it's shorted out it'll allow frequent juice and keep running. And as soon as I put the negative on the battery the fuel pump and buzzers start goin off

 

Exactly. Something in the ignition system is fried. I BET when you start looking you'll find a melted harness somewhere.

 

How does one deactivate the ***** buzzer anyway?