I have a 2005 FX4 with a 5.4L.
I have noticed in the past 3 months that when I mash the go pedal hard the engine misses and there is a popping sound.
My gas mileage has gone down 2-3 MPG.
Has anyone experienced this problem?
I can't afford to take the truck to a dealer to diagnose and hope I can fix it myself.
ANY help will be GREATLY appreciated!

Thanks, Phil

 

Get it scanned for codes first to find out what cylinder is missing... Problably has a coil going bad.

 

how many miles? and have you replaced your plugs? it might be time.

 

I have an 06 f-150 doing the same thing.

5.4 - 53,000 miles - Code for #8 cylinder

I thought it was the COP and replaced it however the problem is still going on.

 

plug or the injector.

 

The truck has about 60,000 miles on it.
The odd thing is that it doesn't do it every time, just once in a while.
Thanks for the help guys.

Keep the info coming, Phil

 

are you throwing a cell when it does it? if so get the code read. you have 1 or 3 choices here.

60K....you might have a bad COP, you might have a bad plug, or you might have a faulty injector.

try to get it to do it and throw a code. moneys tight....been there done that. if it throws a code see which cylinder it is giving you the code. then switch COP's with another cylinder and see if the code will follow you or if it stays on the cylinder. if it follows you and moves to another cylinder then replace the COP. if it stays on the same cylinder that you originally got the code from, you either have a bad plug, or a bad injector. might be cheaper to replace the 1 plug until you come across some money in order to do them all. or do both. a Motorcraft plug is 8 bucks, and an injector ( cant remember but guessing its about 50 or so bucks from orielys )


hope this helps.

 

i had the same problem you have. changed out the plugs, replaced 1 of the COP's and she gets up and goes now.

 

Thank You Shawn.

I know someone here has replaced the plugs on a 5.4.
I've read the horror stories about breaking the plug off in the cylinder head.
How much of a pain in the butt is it to do it yourself?

Phil

 

with the lisle tool, not bad at all. just time consuming. i done mine.

 

Mine was doing the same thing and idling rough when cold.

After replacing the plugs, fuel filter and o2 sensors, the thing is running like new.

The plugs on mine were a royal PITA. Broke 5 out of 8, but that Lisle tool worked well. Make sure you insert the pusher pin (the instructions don't mention it) and you need a deep 15/16" socket for the outer nut on the tool.