the other day i was driveing down the road with my buddie who is supposed to be mechanicaly inclined....well my truck was running really shakey and when i gave it a little gas ( not flooring it) it got WAY worse..
so he told me i needed plugs well we changed the plugs and yes they were very nasty... but that was not the problem.. i figured one of the coils went out and i didnt feel like messing with it anymore so i took it to the mechanic and he did find 2 bad coils well took it home today and it started again and i knowticed a real decrease in power like befor!... could my coils just be going out 1 after another? or could it be somthing else i know these things need to be changed eventually but has anyone ever experienced this and it not be the coils?

 

What year 5.4? The 2005's have an issue with sticking injectors that will cause similar symptoms. If it is an '05 - and that's the problem - Ford has extended the warranty to cover the issue.

 

its a 2004

 

Time to....

Clean the TB
Clean the MAF
Change your fuel filter

If you don't know how to do the above look in the "how to" section of the forum for guidance...

Any codes?

 

Check all the electrical plugs on the coils, they sometimes don't snap back in all the way and one may have worked loose.

 

sounds like a cylinder is misfiring....my guess is like stated. I had a similar issue recently and changed my COPS...solved my problem until a week later when #7 injector stuck open. If it sticks open though you will def know it....DONT restart the engine after you shut if off or you risk hydrolocking the motor.

Good luck with whatever you come up with.

 

Did you use ford or chinese coils? Is the oil level full and clean (could be a bad phaser)? I have seen very few ecm drivers for the coils go bad on these trucks!

 

im having the same problem..

05 f150 lariat 4x4 5.4 173k miles

it drives fine no roughness in 1st,2nd,3rd gear but after it changes in 4th gear at low rpm, the engine gets rough and jerks..

i changed the spark plugs, went away for a lil while then came back the issue.
just recently got code p2104 so i replaced the throttle position sensor, cleaned the throttle body, the MAF sensor and put everything back. Did road test, same problem still persists.

Code went away, i dont get any codes now but its still doing the same thing. Should i go ahead and replace #5 injector? are these symptoms of a failed injector?

btw i just had my transmission rebuilt since it finally died after 173k miles..


thanks guys..

 

You may need one or more coils, salvager. Go on Ebay and look for "DG511". Buy a V-10 set from Global or Uneek for about $140, that way you will have 2 spares.

 

you think its the coils? any easy way i can test them?

i only get the roughness when i am at low rpms (1600-1800) in 4th gear going about 40-45mph and when i accelerate it boggs down..

 

With 173k they are highly suspect, and they are most noticeable under those conditions. It's called a low grade misfire.

 

So these are not the symptoms of a bad injector?

 

Maybe, maybe not. Bad injectors generally have different symptoms - not just under those conditions.

 

im going to order a set of coils in that case, change those and see what happens. I'll keep you posted. thanks for the input

 

UPDATE: 2/19

installed all new 8 COPs, road test under same condition and the shaking with symptoms went away, its running STRONG!! it must have been 1 or more coils bad as mentioned above. Thank you for your help!!!!