My Basketcase Wrangler YJ Won't Start

[SwampSurvivor]

It was a bad buy, I regret buying it entirely.


This is in an 89 Wrongler. Originally a toilet bowl 258, it is a 4.0 swap. Someone HACKED THE WIRING TO DEATH doing this swap in the worst possible way.

Computer is from a 1994 XJ. As is the PDC/Fusebox under the hood. Relays are all new so I suspect they had been having problems before. It started and drove into the garage for me to weld the frame (battery disconnected). Now it won't start. The fuel pump is wired to key on, so fuel at the rail is a bad test. I bought a computer on ebay and am waiting on that to come in.

Some info on what is / isn't happening
- Fuel pump relay does not click , ASD relay does not click.
- Fuel pump relay will click / turn on if I ground where pin 85 on the ASD relay goes in the PDC (with the relay removed)
- I checked a few sensors and I am getting 5v to the sensor when I turn the key on
- There is an upstream Oxygen sensor
- I do not see a downstream oxygen sensor
- I jumped pin 87 to 30 and it still won't run.
- The 15A ignition fuse does come on and off with the key
- Pulled a plug and it does not smell like gas, definitely no injector activity.
- Checked for spark, none.

I don't have any sort of shop scope or any way to check waveform on the CPS to see if that's actually working.

Where should I head next? The Tac and all gauges on this are analog so I do not have any ability to check the check engine light codes or whether or not the tac moves while cranking.

Another option - and one I really don't want to go with - is a 258 aluminum intake and standalone HEI.

 

[daves87rs]

Still thinking computer….just too much of a hack job.

Issue could be anywhere…..

 

[SwampSurvivor]

Found some sellers on ebay selling entire harnesses with the PDC. I think that might be the way to go.

 

[Number_35]

A '94 (or at least the brains) should be OBD I. Is there a key dance you can do to make the CEL blink out a code? (E.g. One long flash followed by three short ones would be a "13" code, which would mean something in Jeepanese.)

 

[Chris142]

I believe it only requires a power and a ground for the ecm to work.. if you are seeing some sort of activity from that id try a crank sensor or at least ohm yours out

 

[SwampSurvivor]

I spent a lot of time this week checking on stuff. There's a lot of cut wires but nothing important is cut. When I turn the key on, the computer is commanding the ground for the ASD relay. That can mean a few things - 1) bad crankshaft position sensor 2) bad computer.

So it's not trying to prime the fuel pump when starting (even though it's wired to key ON, it should still be playing with the relay) . There's still some confusion with a ballast resistor (which neither an 89 wrangler or 94 cherokee would have ...) powering the pickup coil / cam sensor.

I put a new crank sensor in it and still no start. But I don't trust the cheap crank sensors. It also doesn't help that it only had ONE BOLT holding it in. Snagged a new one at the junkyard. But it still wasn't trying to prime when I turned the key on.

Computer came in today and it started right up.

 

[Chris142]

89 wrangler didn't have a ballast. An XJ will