Well, we just drove the truck to Conyers, Ga last week and got back home night for last about 12 midnight, came back across the Smokies with a coat of snow .... and yesterday we unpacked and got the mail, washed the truck, etc. 550 miles each way.

Late last night I was browsing the tech articles here as I enjoyed a cup of coffee, and came across a tech thread about a "Fuel Pump Driver Module" located on the back side of a crossmember under the bed.

https://www.f150online.com/forums/ar...placement.html



I read it and one poster posted of his on his 07 being "gone". Today I backed the truck up on my shop apron, dropped the spare, removed the module and found it had some minor corrosion.



I cleaned it off and applied a coat of clear laquer.



I cleaned the frame crossmember area as well, minimal signs of corrosion there.



I applied a couple coats of paint (no picture of it painted, but I did) and let those items dry while I tackled the issue of stand offs.

I took two longer M6 x 1.0 x 40 bolts and chuck them in a vise with aluminum faces and cut the heads off and then filed the ends smooth. Then I installed a Nylock nut on each leaving me about 1/3 of the threads to go into the frame crossmember, the rest above the nut as a stud. I installed these studs and snugged up the nuts against the crossmember.

I applied more clear laquer to the area on the studs and nuts against the crossmember.

I cut two pieces of 5/16 fuel line a little longer than the height of the nuts and slipped over the nuts., then slipped some 1/4" washers in place, set the module in place and saw it had about 3/16" between it's back and the crossmember. I slipped two more 1/4" stailess steel washers over top and another pair of 6mm Nylock nuts which I snugged down.

I thought I was done except for plugging the wire in and putting the spare back.





I went to plug the harness connector C433 back in place on the mudule and I felt something ***** my finger. I felt around the connector and suddenly the light blue wire with red tracer was broken about 3/4" from the connector where it vanished into the plastic loom. I know the wire had to have been partially intact as I drove the truck to the apron, and I never pulled on the connector ..... but the wire broke.





Got my magnifying glass out and some light, the blue/red wire had been chewed through and appearantly a single strand, maybe two ... had held it. The orange wire was chewed too, bare copper showing and several strands damaged. These two wires are 20 gage, very small and go to terminals:
1 (blu/red _ Fuel pump driver module monitor)
and
6 (org _ Fuel pump driver module control).
They are side by side in center.

First thought .... "Damn".



Bad squirrels.



Then immediately .... Well, this isn't so bad, far better to find now, here, instead of on the interstate at 10PM in holiday traffic 250 miles from home?

Bad squirrels.

Remove some factory tape and open up split loom and free up wires and find some in my wire box close to same color and some shrink tube and splice in pieces for both these wires. Splices prepared, soldered, shrink tube shrunk, wrap with a few rounds of good Super 33 tape, close loom, tape up, hook up again ..... took a few moments to write, a couple hours laying on back reaching and trying not to damage wire in connector end.

Bad squirrels.

Finish taping loom all way to connector and shoot it with fine coat of clear laquer, clean spare up, address air pressure, put in place, start and move truck back to it's carport.

Bad squirrels.

Last year I had to repair the whole harness between the rear tail lights of my '77 same deal. All in all, a productive afternoon doing some preventative maintenance that may save me a bundle compared to what could have happened, and a good lesson as to why the manufaturer goes to such great lengths to secure wire harnesses in place.



I also noticed that the factory method of bolting the module to the round crossmember in a place where it's not as flat as it looks stresses the modules housing, mine wasn't bent or broken ...
... but if one were to overtighten the retaining screws that factory used it would have broken it as the mounting ears were not fully against the crossmember.

 

Nice post!!!

 

OP - why can't you just use longer bolts and put a couple washers between the module and the frame???

I don't understand the need to cut off the heads and use a series of nuts to do all the mounting.

I haven't looked at mine yet... maybe there is something I'm missing???

 

Mr. Bear - feed dem squirrels





Great post!

MGD

 

Click the OP's link in his post and you'll see the replacement screws that Ford is providing with the module. Looks to me like the intent is to put an air gap between the frame and module, so it can't trap moisture and cause corrosion. Washers would achieve the same purpose. I may need to look into doing this with mine.

 

I've seen the picture of the bolts... I even called the ford parts department to see if I can order them, but according to my local dealership you have to buy the entire kit for $162.50 (new module and bolts) ...I am hoping my current module is OK when I check it.

I think I'm going to just use M6 bolts with some washers and a M8 nut under the module to space it out.

 

get the bolt kit number and try ordering it through tasca.com

 

Very good post and information. I gotta look at mine and see whats up under there.

 

You should, mine just went a few weeks ago. You deal with the same weather I do and my truck is a year newer than yours.

 

Oh jeez!! Well its suppose to be sunny here by Tuesday so looks like I'll be droppin the spare real QUICK!

I always high press. wash underneath everytime I clean the truck. Although I do understand that most of the time it probably wont get clean around this sensor. I don't even know if it helps??

What do you think?

 

You could if you wanted to, but I was laying on my back, working on a module that mounts at an angle facing upwards at near 40-45 degrees, and I started to do just what you suggested when I happened to recall the pic of the Ford stud kit and it occurred to me how much easier it would be with studs to slip a washer on under the module and then just slip the module on, it doesn't fall off.

I used washers between the module and nut because the holes in the module are bigger. My use of nylock nuts and a stud locked to the frame and then two more nylock nuts means I didn''t have to tighten the nuts up but just so tight. Like I said, the frame area is not "flat" and bolting it tight can stress the aluminum.

You can see the corrosion occurs at the points of contact between the aluminum back of the module and the steel frame. I saw some pics posted in another thread where tghe aluminum was eaten away really bad and broken open.

MGD, Like the pic!

 

I also wash under my truck regularly by spraying as well as running a sprinkler under the truck. Made no difference. I had to replace my module on my 2007.

Good to see this thread getting attention as this hidden problem can leave you stranded at the worst possible time.

 

I completely forgot about the FPDM thread I read from last year. I am now having hesitation problems when lightly accelerating at around 40 to 50 mph and I am wondering if this could be causing my issues. Originally had a misfire which came up as a P0307 code and turned out to be a bad COP which I replaced, but I am still having the hesitation problem, though it is not as bad as before I replaced the coil. Going to be ordering all new COPs, plugs and new fuel injectors (injectors mainly because the truck is an '05 and they have documented problems with this model year), so I am doing preventative maintenance as it has 187,345 miles on it now. Guess I'll be crawling under the truck this morning after the rain stops to check the FPDM and possibly ordering one of those if I can't "save" it like tbear was able to. Nice write up btw tbear, and I am still laughing at that pic MGD!

 

I just picked up my truck yesterday morning for this exact thing. I feel better now, I was getting really worried about what I was going to spend that $465 extra I had just laying around.

Have you noticed a difference in fuel economy with a new module? I could swear that my economy has improved by 1-1.5 MPG after the module was replaced (according to my Scangauge II)

 

checked mine yesterday... lots of corrosion but no cracks. After cleaning up the corrosion I put a straightedge on the bottom of the module and it looks to be bowed about 1/8 inch.

I wire brushed the bottom real good and then smeared a good coating of grease on it.

I put it back in with M6 x 1.0 x 40 bolts. Mine had the regular head on them, so I put a M6 lock washer, M6 washer, and then a M8 washer under the head. Then the module flange, then between the module flange and the cross beam I put a M8 washer (so it will slip freely over the M6 bolt) and a couple washers.

This spaced it out a good 1/4" or so... hopefully this will keep it from corroding to the point of failure.

I think this thread needs to be a sticky!

Check your modules now to save 150 bucks (or more since you'll probably need to be towed when it dies)

Thanks to Tbear and the others for letting us know about this issue!