Help! No start, fuel pump constantly running

[jondf]

I have a 1993 Ford Explorer sport 4.0 5 speed. It seems to be eating computers. When I turn the key to the on position the fuel pump constantly runs and wont just prime. It also will not start when it's doing this. I've put several computers in it and it will act right for a little bit but then will go back to doing the same thing. I have a 94 for parts and tried that computer once and it will prime and then start. Ran horrible but it did start. Does anyone have any input or experienced this with theirs? I've checked wiring diagrams and have a factory service manual but didnt see anything obvious. I've changed the pcm and fuel pump relay. And it's still doing the same thing. About 5 years ago I put an airtex fuel pump in it and wonder if it might be drawing too many amps and shorting out the computer. Any help or insight is appreciated. Thanks in advance!

 

[Mr. Alligator]

No experience with this particular situation, but does sounds to me like you need to change the fuel pump.

Good luck.

 

[410Fortune]

Airtex is not the best I have had issues with those

I would check the wiring and fuel pump power / ground wires at the gas tank conector before dropping the tank. Meaning unplug the fuel tank and test the signal from the PCM/relay/fuse
this way you can determine if the fault / short is inside the tank

If the fuel pump and tank wiring check out then I would start to suspect a short in your wiring, somewhere in the EEC relay, computer power feeds

 

[Centaurious]

Don't forget the PCM grounds.