I have a 1990 4x4 XLT, 5.0/302 with two fuel tanks. The problem started a few weeks ago, driving down the highway, when the truck starting "losing power" (seemed to be losing fuel). Truck died, then cranked over with no fuel seeming to pump. 30 minutes later it started right up, then promptly died 2 miles down the road. I switched to the rear tank, and it ran fine for a week.

I assumed that my front fuel pump went bad since the rear seemed to be working, but then the same event occurred on the rear tank after one week. I replaced the fuel pump relay, and the truck started right up. Worked for 10 minutes, then died again. I replaced the eec power relay with no change. I then took the chance that both pumps happened to fail at the same time (dumb idea), and replaced the rear pump. No change. Then starting tracing wiring. As far as I can tell the EEC power relay is fine, and is sending power to the fuel pump relay. The fuel pump relay is sending power out to the EEC, but nothing is coming back. Do I have a bad EEC, or what else should I check?

One other important note is that a few days before this all started, my starter remained in the engaged position after starting it, and the chain reaction melted the battery and the ground cable. I replace the battery, ground cable, starter (and the solenoid for good measure). I'm worried that perhaps some further electrical damage was done.

I don't want to replace more parts unneccessarily, but I'm not really a mechanic, just an amatuer trying my best. By the way, where is the EEC?

Thanks for any help.

 

Hi,
I have no experience with the consequences of the starter problem you had.
Did you suspect the fuel filter?
BTW, the EEC is between the walls behind the parking brake assy. You should see the big EEC connector under the hood at the firewall, driver side most right.
LoL Dieter

 

I agree that a new fuel filter is in order.

 

I replaced the fuel filter about 3 months ago. Thank you for the suggestion.

I found the ECC and pulled it out. I'm having trouble finding anyone who can test it.

Any suggestions?

 

I believe your ground connection has a smaller wire coming off of it, and this is the ground for some of the computer system. Some guys on here before had a problem with their fuel injection, and this ground wire had a connector that was corroded. I wonder what condition yours is in, if it's even there after the melted cable thing.

 

Thank you for your reply. I replaced the ground cable from the battery to the block when the battery melted that day. There wasn't any other ground wires that I remember. Where would I look to see if there should have been?

 

Look for any black wires with a white strip that look like they don't have a home.

 

I found the ground wires coming out of the harness right in front of the battery. I reattached those to the frame with an additional ground wire to the negative battery post.

and....

It's fixed! Thank you for your help.