Guys I'm having problem with my wiring harness on my modded 91. I can't get the car running long enough to even get it home, so I'm going to have it towed. Anyway, I thought there was a problem with the dist./Igniton/coil, so I replaced all of it including the module and pickup coil. I got the car running but then it acted up again and kept dying. Some wire in the harness is shorting out my tach signal and also is interrupting any spark. The car won't even start now and when you grab wiring harness where it runs into the firewall and if you shake it, you get all kinds of interesting noises. You hear things like the fans coming on and the fuel pump relays go crazy. I'm about to rip the entire harness out and have a friend diagnosis it, but I'm not counting on a rewired harness to be very reliable. I'd like to get a used harness out of a 90-02 SD car, but I can't find any at all. I then went on ebay and saw this.

http://cgi.ebay.com/ebaymotors/ws/eB...spagename=WDVW

The thing is I don' t need all that under the dash wiring, I need just the wires to feed all my engine components and accessories. I've heard there are problems with the stand alone harnesses and that's why I'd rather get my re-done or get a used harness. Any suggestions?

 

Make sure the bolt in the center of the firewall connector is tight, sounds like what happens if you leave it loose and wiggle the harness.

 

I concur

 

Do you guys thing that if this bolt is the problem that's why my spark is getting interrupted and why my car won't run? My tach signal keeps going out as well any signal from the ecm, which controls spark advance.

 

In a word...Yes. you probably have other things that aren't working that you haven't discovered as yet.

 

Things such as what??? I replaced my ignition module, coil, all components in the distributor, cap, and roter. Do you mean there could be other problems in the harness? If so then it's obvious that I have to yank the wiring harness and go through it. Now the question is what should I do if the problem is in the harness?

 

If the harness is loose there could / should be other things not working.

Try turning the key on and turn on everything... blower, stereo, lights (interior and exterior) and wiggle the harness and see what else stops working.
If the harness is to blame you can take the bulkhead connector apart and see if there is corrosion in it also check for recessed pins also check for pinched wires. If everything looks good try reconnecting it and running the bolt down tight and see if the car will start and stay running while you gently wiggle the harness. If it doesn't you'll need to get a schematic and VOM and start chasing electrons.

 

Thanks Morley. The car is at my friend's, who actually does a lot of my work. I'll try to get out there in a few days to see what happens. I'll be sure and post what I found out then.

Joe