Hi all. Here is a little read into my problem. I hope I am detailed enough and clear enough for you all to understand my dillema.

It started completely unexpectedly about a month ago when I was driving around 70kmh while cruising. I would get a few "jerks" of a sputter, then was able to drive a km or 2 before it did it again. I drove to a friends and he got in, and the sputtering episode was over.

Since then, I cannot simulate the way I was driving to make it sputter for any mechanic, but I have been getting sputter on and off the last month.

The one time I got in the truck and started it, put the truck in drive, and it sputtered for a few seconds. I wasnt driving at all this time. This was the only time It sputtered in a stading position.

Here are a few points to maybe help narrow down what happens.

-I am usually driving around 70-90kmh
-I am usually under no loads (not towing, hauling etc).
-My mileage seems to be getting worse.
-this was normally happening not only when the engine was warm, but when it was warm outside and I was driving it for a longer period.
-When I started driving my truck I calculated around 16mpg city. I am currently getting around 13-14. I was on the hiway for around 250 km and got 14mpg. Seems I get better mileage when puttering through the city than when I am on the hiway.

I had the truck in to a dealer 2 weeks ago. They did an injector flush, new sparkies, number 5 coil, and took me for $780, saying the problem is fixed.

A few days ago, I was driving on the onramp to the hiway accelerating around 90kmh and for around 4-5 seconds I was sputtering and jerking so bad I thought I was done for. The truck finally recovered and again, havnt had any episodes since.

The dealership says their electrician doesnt know what to do, and would need my truck for 4-5 days to try to see the problem for himself.

I can only think, as a non-mechanic, that it is something to do with some sensor, possibly a fuel, and/or oxygen sensor.

Any thoughts, comments, questions are greatly appreciated!!!

2005 F-150
4.6
88000km
gas

 

A couple of things come to mind. If we had some codes it would help. Since the plugs and a coil were replaced, I would suspect either coil boots or fuel injector(s) leaking. If there is a P0191 code I would suspect the fuel pump driver module is giving up the ghost. Any of these or other things could cause a drop in mileage.

 

On my service bill, there is an area where it says "code" but there is no code.

Besides spark plugs, coil and injector flush, theres nothing else.

 

Apparently they did their work on your truck by symptom rather than by code. They would have charged you for a code scan had one been done. And most likely there are some codes or a code in there. I would go back to the dealership and complain that they have not fixed the problem. If they need the truck for 4-5 days request a loaner vehicle. They should be able to install a data logger and have you drive it for a week or two to see if the problem comes back. If it does it would be recorded in the data logger. It sounds intermittent and that can be hard to trace. But the symptoms that you decribe sound like it could be the fuel pump driver module. It is located on the crossmember directly in front of the spare tire. They usually throw a code and mess up when the truck is warmed up. If that's the problem, eventually it'll quit and won't restart until things cool off. These trucks are prone to have problems with the FPDM. If your battery is getting weak or there is any connection problems that also could pose symptoms similar to what you are experiencing. Good luck and let us know how things work out.

 

When I was at the dealer, They basically said its a different problem. ???? They also had the new coil and plugs as a "start" to fixing the problem.

I already pulled out the FPDM and it looked like it was in good shape. The seal was also looking good. Is it possible to open it up to look inside, or will it wreck the seal? Could be there is a small hole somewhere where I cant see and its letting moisture in.

The connectors seemed to be a dark brown instead of the silver. I am thinking this could be a small problem with the connection. I cleaned it all up and put it back. Hard to tell if its fixed at all. I do have to go out of town on Thursday, so it will be interesting if I actually get better mileage. (I understood your first reply that this component would do so).

Here are a couple of pics (if they work) the one shows with arrows where the contacts were dark brown with stripes from the female side.



Uploaded with ImageShack.us


Uploaded with ImageShack.us

 

Those connections do look bad. That might help with the missing or bucking when warm problem. I don't know if that will help mileage or not. It might. On my wife's Taurus it didn't change mileage any when I replaced the fuel pump ( the FPDM is part of the pump on the Taurus instead of separate like on our trucks). It's also possible there is a small hole in the module letting moisture in. You can always spray the module down with the garden hose and see if the problem is back when warm.

 

Thanks for your input. I will let you know how the mileage may be working out. I have to go out of town, about a 3 hour round trip Thursday, so I hope to see some results.

 

Sorry for the late response. I didnt do any better mileage on the hiway. It seems to me that I get better mileage in the city. Can this be?

I noticed a couple other things.

It seems to me that the faster I go, the less power I seem to have. I can be driving on the hiway without cruise control, and it seems I always have to hit the gas, as I seem to be decelerating all the time.

The other day I was in a parking lot just coasting through and without me hitting the gas, the truck acted as if I DID hit the gas. I had to hit the brake.

To me it does seems as if its still a problem with gas flow.(Again, a non-mechanic conclusion). I am almost at the point to just go out and buy a new one to see it it work. Of course if it doesnt, then I dont know what to do.

 

Just as an fyi, which may or may not be the source of your problem, there is an extended warrantee for 120,000 miles on '05 models for fuel injectors that are defective.

 

Oh really. The guy at Ford failed to mention that as he was taking my $780. How can I tell if they are bad? Do you have any info that i could bring to Ford to get this looked after?

also, I was just about to edit my post above. I have also noticed that when I am driving thru a parking lot for example at about 10-15mph, evertime when I hit the gas I will hear a "psst" before it actually accelerates. dont know if I am being paranoid now about everything, or is that normal.

I am reading more on these forums, and maybe I have a pressure leak somewhere?

 

I can scan and email you the info I have. IM me your address.

 

You may have a vacuum leak somewhere. There should not be any psst sound when you mash on the accelerator. Double check for codes also. There could be a problem with the drive by wire system or the tps.

 

Uhhh...... anyone suggest maybe the fuel filter? If it were me and I was sputtering and getting bad fuel mileage, the first thing I would have looked was the fuel filter, especially if it did it even once while idling and not actually driving

 

That was the first thing I did.

I was just outside at my truck and wenth through all the wires and hoses to see if there were any breaks, cracks or leaks (engine running) and even wiggled different stuff, and no change.

I am thinking of buying the FPCM but on Ebay they dont ship to Canada. Every parts store I checked doesnt have it. I guess I have to try ford.

 

Okay, you didn't mention it which is why I had to ask, damn wish I had some other idea. I recently replaced all of my injectors and what a world of difference it made in how the truck ran as well as the fuel mileage I am getting, did it myself and it only cost me $200 in parts. I also replaced all the COPs at the same tome and they were a little pricier. I see you had yours flushed (or cleaned) and I don't trust that as much as replacing them. Your problem however might be a little deeper than that.