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Projext "V8 XJ" Build

So weird issue is back again.

I hook the GM fuse box into a relay. I trigger the relay with the battery. Everything works. Pedal works. Jeep actually runs pretty well.

Hook the same relay trigger into the jeep coil power wire. I get no pedal. I found out why. The coil wire is triggered using the ASD relay.

Now same thing again but the trigger is hooked into the cig lighter power wire. I get pedal now, but no spark.

Weird issue. Again if I hook the relay trigger directly to the battery it works perfectly.

Suggestions?
 
So weird issue is back again.

I hook the GM fuse box into a relay. I trigger the relay with the battery. Everything works. Pedal works. Jeep actually runs pretty well.

Hook the same relay trigger into the jeep coil power wire. I get no pedal. I found out why. The coil wire is triggered using the ASD relay.

Now same thing again but the trigger is hooked into the cig lighter power wire. I get pedal now, but no spark.

Weird issue. Again if I hook the relay trigger directly to the battery it works perfectly.

Suggestions?

I know I'm quoting myself on this, but is there a keyed ignition that stays on with the key in the "run" and "start" position? I wonder if the coil and cig lighter relays I tried are somehow not functioning in the "start" position.

If they're not i'm just going to run a switch to the battery and any time I turn on the jeep I'll flip the switch to start up the GM PCM. It'll basically be an ignition switch...

I know it should run off an ignition positive source but I just can't figure out why. The guy who did my wiring harness just said "it must be an issue with the Jeep wiring". Thanks dude.

**EDIT - I wonder if there's a key+ that powers up the Jeep ECU. I'll have to check if that wire would work to trigger the GM fuse box.
 
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*facepalm*. I just looked at the ignition switch wiring. I didn't even realize it was in the manual. I can't believe I missed it. So fuse 8 at the junction box is a spare fuse and is on with run and start. So I ordered some mini fuse taps and we should be all good.

Man do I feel stupid
 
That sounds nice dude :)

As far as your wiring... I know you already seem to have it figured out but I have an FSM here if you need me to scan some pages or get you some info. The start/run wire I used comes from the fuse block in the passenger kick panel and it goes through the firewall on that side of the Jeep.

Thanks for the offer. I have a FSM as well. Like I said before wiring is not my strong suit. I've learned a lot with this project and how wiring works, but I still don't like it.
 
So all the wiring is complete (I still need to wrap and loom it) except for the keyed GM PCM. I ran a wire through the firewall I just need to get the parts I'm waiting on.

I need to mess with the radiator mounts a little. Fill the radiator and transmission with fluid and we should be good. I might be test driving it this weekend!

Other than that I have to button up the EVAP hose situation. I ran the stock jeep hose from the charcoal canister to the firewall. Now I need a way to get a 1/2" hose to 3/8". I'll probably just do the same thing I did for the brake booster and get some barbs from Home Depot.
 
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What kind of hose? You could use brass fittings if it's the soft hose kind.

Yea that's what I'm going to do.

Well, no driving this weekend. Nipple on the radiator decided it wanted to strip itself. I was taking it off because I need a 90° fitting to clear the radiator support. I'm either going to drill and tap (it's pretty thin aluminum though). Or get it welded.
 
Yea that's what I'm going to do.

Well, no driving this weekend. Nipple on the radiator decided it wanted to strip itself. I was taking it off because I need a 90° fitting to clear the radiator support. I'm either going to drill and tap (it's pretty thin aluminum though). Or get it welded.

Oh that sucks man. Good luck on the fix.
 
So here's what it looks like. Just need to get/find the rad cap, fill coolant, fill transmission, and fill PS fluid and I could take it for a spin!




Oh, and my Optima finally died! After 2 weeks worth of cranking and using the interior lights! Pretty impressed!
 
Nice dude. I was working on mine tonight too. Got a couple codes to figure out but it seemed to run good. Stoked you get to go for a test drive soon :)
 
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