hi everyone.
Im looking at my buddys 87 f250 (300 6cyl efi). If you turn the ignition to ON the fuel pump runs continuously (it would run until the battery died as far as i know, definitely NOT the 2-3 sec its supposed to).
The truck wont start on its own, but it will start off starting fluid and continue to run, but with no power what so ever, and if you open the throttle all the way it'll stall. I checked the fuel pressure and it reads about 55psi without the engine running. Only thing i replaced so far is the fuel pump relay, which made no difference.
From what i read on this forum, the fuel pump not cutting off is a "classic sign of a bad computer", from what i describe here (and below i suppose, unless you guys think its unrelated) does this sound like a bad computer? i want to be fairly sure before i spend 120 bucks (thats from advance autos website) of my buddys money.
Also, (this may or may not be related) if the truck is run with the iac plugged in, it wont idle down, it basically idles at redline (truck doesnt have a tach but basically it idles WAY too fast), if the iac is unplugged it'll idle down somewhere close to where it should. The iac was recently replaced (but not by me) so as of right now im assuming its not physically stuck. Could a bad computer affect the function of the iac as well?

Thanks for any help.

 

Unplug the computer, turn on the key, if the fuel pumps do not run then it was the computer.

 

do what subford says, but it sounds like the computer.

 

thanks a lot for the responses.

ok i unplugged the the computer and turned the key on, nothing happened. I went ahead and pulled the computer out and opened it up. It smells burnt, and one of the chips is obviously burned up, the outside of the box also has a sort of corrosion on it as if it had been getting wet...

But anyway i took a picture so you guys could see.

<img src="http://i456.photobucket.com/albums/qq285/ticklishballs/fordcomp.jpg" border="0" alt="f250 ecu">

 

A lot of the time when someone reports something burned up in the computer is either after they wash the engine or got water on the computer plug somehow.

 

yeah he said it drove fine on the way home from work that day, then it rained like crazy that night, then it wouldnt start in the morning. so it makes sense i guess. thanks again.

 

Fill the plug with dielectric grease when you put the new one in.

 

and make sure the battery is disconnected before putting the new cpu in.