Broken EEC box?

[Blue91Ex]

Hey guys, i have been wondering about this thing since i bought the truck..
That little black plastic box (or two boxes stacked rather.) on the left of the airbox is broken on mine, truck runs fine, but the bottom box has broken off of the mounts so it just flops around underneath the top box. I heard it click a bit (prob from shorting out the contacts? on top of the bottom box) while i moved it around to clean my air filter. anyway is this the computer for the truck? can i still get a CEL when the bottom contacts dont connect to the top box? Or get codes?
pics:

you could see how the bottom one is no longer mounted to the side..

thats what the contacts look like, and as you can see it moves around all over that space underneath the top box.

any clue whether this is important to have mounted right? will i still get idiot lights and CEL etc with it liek this? what problems might it cause?
thanks guys!

-Blue

 

[arco777]

Your computer/EEC (Ford term is PCM) is located inside the cab, behind the passenger front kick panel.

 

[Blue91Ex]

okay, thanks for the info, so what is this box part thats is broken off? also i have found that when you shut the truck off you hear a low humming sound and sometimes a little pop noise from that area of the truck and sometimes right after it goes off, if someone slams a door on teh truck it will make the noise again but shorter... im asuming that would be the contacts shorting? also sometimes the truck doesnt like to start cold and sometimes i run it for an hour or so driving and then it starts like crap warm but if i let it cool for 20-30 mins it starts on like the second crank.. idk what is going on with this truck lol. runs just fine other than that though..

 

[Blue91Ex]

shameless bump

 

[Fowlbal]

:exp: I think your talking about the power distribution panel. Search user name (bensbest) 2nd post.

 

[awood]

Yes, the power distribution box is nothing but a holder for fuses and relays. If you're hearing clicking from inside, it's likely a relay energizing or de-energizing. The cover is removable in case you need to replace a fuse or relay. Release the latches on the ends of the box, and the cover will come off. If it's flopping around, it's likely just the box mount has broken off from the fender, and it's resting on the wire bundle that feeds to the box. If everything is working, I wouldn't worry about it.

 

[Blue91Ex]

i remember bumping into it when i was cleaning out the airbox and air filter and it woul short and pop quietly, i figured ti was those contacts touching similar ones on the top box?
when i shut the truck off i hear a long humming/hissing noise with intermitent little pops when the engine is shut off, and if it stops and someone slams a door it will start again for a few seconds...
thats the part im conserned about.

 

[awood]

With the box loose and flopping around, there could be a wire that's chafed through somewhere and shorting. If so, that would require some digging - probably outside everyone's normal experience with the Explorer.

 

[Maniak]

On the 1991 and 1992 there is a box under the fuse box that holds most of the relays for things like ECM, Fuel pump etc. On the 1993 and 1994 they moved the relays up to the same level as the fuses.

Anyway... Once you turn the truck off there should be no noise there..

If your still hearing noise from that area after you turn off the truck my bet is your have a bad/sticking relay. More than likely its the Fuel pump one..

I don't have my diagrams with me (@ work) but if you pull the Fuel pump relay and the noise goes away your on the right track.. Just replace the relay.. If you don't eventually it will get stuck on and drain your battery.

~Mark

 

[Blue91Ex]

we thought it was the fuel pump at first but then i noticed it came from the area with that relay box so i figured it was those metal contacts on top of the bottom part touching possibly similar contacts on the top box. where would i find the relay/wire diagram? is it in the user manual?

 

[Maniak]

we thought it was the fuel pump at first but then i noticed it came from the area with that relay box so i figured it was those metal contacts on top of the bottom part touching possibly similar contacts on the top box. where would i find the relay/wire diagram? is it in the user manual?

I'm not saying its the fuel pump making the noise but the fuel pump relay which is in that box.

The box should not be making anynoise once the vehicle is off. As you turn it off it will make clicks but that is the relays de-energizing..

If there are metal contacts sticking out from the fuses and/or relays they could be making contact but you can just tape some cardboard on top of the lower box so it can't short across the wires under the top box.. BUT, I don't remember there being any metal on top of the lower box that could short out the wires above it anyway.

~Mark

 

[Blue91Ex]

itr shows the metal contacts in the pictures. they are the lighter grey parts making a squared U shape.. idk if they are contacts or just the tops of the relays. i guess i could try taping cardboard on top and see if that fixes the problem, if not i guess i will have to tear it apart and see if there is anything wrong...

 

[awood]

On the 1991 and 1992 there is a box under the fuse box that holds most of the relays for things like ECM, Fuel pump etc. On the 1993 and 1994 they moved the relays up to the same level as the fuses.


~Mark

Hmmm, I never noticed that difference before. Thanks.