I bought my 2004 F150 back in Novermber 2012 it had 144k miles on it. It had been maintained religously at a Ford dealer as it was a commercial lease truck for a building contractor. The previous ownder had the plugs changed at 96k miles. They broke at least two, and had to pull the head to get it repaired. I am not sure why they didnt use the removal tool. The head was repaired at a machine shop and new ford parts installed per a standard head removal. The guy had it back in the garage for a miss after this work with a low RPM miss in Overdrive. They diagnosed it as cylinder 8. They replaced the coil on cylinder 8, and the spark plug twice on cylinder 8. The problem still existed, and existed when I got it. When I got the truck i noticed it had 2 brand new COP and the rest seemed to be original. I bought a new one and replaced them one at a time, until I found what I thorught was the culprit. It ran great with no misses for about a month. Then it started to come back slowly. It got worse and worse, but somedays ran better than others. Then one day, going up a hill in O.D. at about 50 mph, it starting bucking and missing horribly. I stayed at that RPM, and pedal intentionally to keep it missing in hopes that it would eventually throw a code. The Check engine wrench eventually started flashing. The CEL stayed on. I read the code at it was p0357. Which is Ignition coil primary/Secondary for cylinder 7. I replaced that coil, along with the rest of them, and the problem still happens although, the jerking was not near as severe. It was like a dampened less severe jerk when it was missing in overdrive at low RPM when going up a slight hill. Now just recently the bucking/jerking has gotten worse, and I can even get it do it in drive, if I force it into overdrive lockout. It will also occationally do it at WOT too. The other day, the bucking/missing got severe again, and I held it there to try to get a code, and I did. This time the code is a P0308 pending code. So this is the same cylinder that the guy before me had the problems with.

The truck now has 154,000 miles on it. Runs smooth and idles smooth except during this bucking/jerking/misfire episodes.

So, all the COP are brand new OEM ones, and I still have the problem. The problem cylinder now seems to be #8, which should have the plug that was replaced twice (last time was around 105k, if I rememeber correctly).

The only other hint, is that I called the dealer and asked them what was the last thing they told him after replacing the plug the last time, and he said that the Ford Tech said the cat(s) needed replaced. They were showing readings that showed they were not right. I dont remember if it was one or both cats. The previous owner did not get that done, and traded it in soon after that. The Ford service advisor said the cat going bad, has caused severe engine damage in the past on those motors. BUt I have never gotten a catalytic code of any sort, so I took that as a bad diagnosis (a guess from a Ford Tech out of answers).

So I am not sure what to do next. I read about the Fuel pump driver module issues. But not sure if my symptoms are common for this issue.

The plugs would be my next guess, since they are coming up on 60k miles. BUt the one that was missing from the last code, is the plug with the least miles on it (I would guess 45k). I am not sure I have fixed anything at this point, as everytime I think I fix something it seems to come back within a months time or less.

I have cleaned the throttle body, and MAF sensor, and put a new air filter in. I have run about 4 tank fulls of gas with fuel injector cleaner in them.

I have a common problem but a unique twist to it.

Anybody got any ideas or suggestions on what route I should try next?

Also there is a TSB back in 05 for a driveability issue with these models. I am sure mine doesnt have this flash update. Dont know if that could help out the issue or not.

Sorry I have so many question, and please excuse my long winded rambling. Just trying to put 9 months of trials and failures and experience down on here to give as much information so somebody might can help me out.


Thanks for you time,

Brian

 

Read the last post:

https://www.f150online.com/forums/20...ease-help.html

 

Thank you very much for the help. I read that one this morning before posting. However, I have gotten the P0357 code only one time. And it was bout 4000 miles ago. And it has been missing bad since then, and has never shown another code at all, except the other day when I got it to miss really bad, and got it throw the P0308 code. I have nver gotten any other P035x codes or any other P030x codes. Those two codes are the only codes I have ever gotten. The truck runs normal if you keep it out of overdrive and 45-55 mph, or never go WOT. I think we have similiar problems, but not exactly the same. If it was my coil driver circuit part of the ECM, it would just be on cylinder 7, and my missfire was recorded on cylinder 8. His coil drivers seem to have gone out all t once, and truck ran terrible.

 

I just had my Fuel Pump Driver Module go out. Drop your spare tire and check it. Even with new COPS and plugs, my 50mph range still had some surging. I just took it needing a tune.

When I replaced the module, it was like a completely different truck. There was enough corrosion on some of the resistors and PCB to screw with the electrical signals I guess. But it is a $100 gamble if the module looks fine and not falling apart.

 

Ok. I found it on Amazon for $54 with free shipping. I had it in my cart ready to buy, but held off. I think its worth a $54 try. Thanks for the help.

 

20 minutes of time could save you $60. I would say inspecting would be better of than just throwing money at the problem at this point.

Changed the fuel filter recently? Tried swapping the injector on the misfiring cylinder?