Will not start after installing battery backwards

STOROVICH1

MEMBER
1988 FORD F-250
5.8L
V8
4WD
AUTOMATIC
699,428 MILES

I placed battery in backwards to start. I then replaced battery, soleniod, fusible links at the solenoid and the ignition lock. I also lost keys after the battery incident and before I got to try and fix whatever I messed up in hooking battery up wrong, so the ignition could be the problem now but wasn’t apart of it to start. Last night after I put in the replacement relays in I tried to turn it over and it stuck in the start position even with key out of ignition. I had to run around and disconnect the battery to get it to stop cranking. Did I fry my EEC? Is there a way to test it? I’ve got the ignition control module but it’s a $50.00 part and once I put it on I can’t return it if it’s not the right part. I’m just chasing this and throwing parts at it and I’m still walking to the parts store. So if you can please help. I’m getting fuel up top, but don’t hear pumps at all even with ear pressed against tank from underneath. I’ve gat fuel at stater and smell it when cranking but no pump. And there is absolutely no spark. I replaced the relays for fuel pump and ignition also. But it stuck cranking after I did that.

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,758 POSTS

Hi,

Did you burn out the fusible link or simply replace it in the event it was damaged? As far as the starting system, it is very basic. Are you sure you have the wiring correct at the solenoid? Is anything touching the two posts which would cause power to be constant to the starter motor?

I attached a pic of the starter system wiring schematic. Take a look at it and you'll see there isn't a lot to it. At some point, power is being supplied constantly to the red and blue wire at the starter itself.

Check at the starter and relay for any crossed wires. Also, if you connect the battery, dies it start cranking right away, or do you have to first turn the key? If you have to first turn the key, I suspect the starter relay you got is bad.

Let me know.

Joe

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