Cstrickland33

Hello everyone. So here is another misfire thread. My wife and I are pregnant, and we were headed to the baby dr today, about an hour and a half drive. An hour into the drive my truck starts to shake and is running real rough with the check engine light blinking. I pull over on the side of the interstate and turn the truck off and back on. Thinking it was just a loose wire or something since I've only had the truck a month (yes, one month!) only to see it come back on. I have an edge programmer in it (no clue how to use it since it came with the truck) but I was able to read the code the engine was giving me which was a cylinder 2 misfire. The coils have been replaced before but I'm not sure when. Truck is in super great shape besides that. I turned it back on and finished my drive to the dr without it happening again... and I mean running rough. It happened again on the way home about an hour into the drive again. Truck is a 2004 lariat 4x4 with 131k on it. So here are my questions...

Is this something I should go ahead and replace the coils (again) and the spark plugs?
Could it be something as simples as a fuse or a lose wire causing this?

fordmaster302

Depending when the spark plugs were swapped you need to check the one in cylinder 2 ASAP

It could be the spark plug , coil or fuel injector on cylinder 2 start with swapping the coil from cylinder 1 to 2 and see if it follows the misfire

SCORGE

Do all plugs.

redfishtd

New plugs sp546 ,new boots and springs Check all connectors locking on . Clean all connectors with contact cleaner ,Clean all cop connections real good. Torque all plugs in 25 to 28 foot pounds .Do a hosp clean install .
If these are orig plugs you need to have lisle plug extractor on hand . You must start with a good plug job .
If she throws any codes, list them here so the folks can determine what they mean . Codes do not give you this is the problem --replace this ,some are the result of other factors . .
Example- She shutdown and oil light was on . All shutdowns will result in low oil pressure ,and there is no low oil shutdown on these trucks. Its just a result of whatever shut it down not the cause .
Factory cops rarely go bad but they do corrode up on terminals . If oil /antifreeze leaking in sparkwells it will short it out. Plugs are only good for 60k . Oil changes not more than 5k ,this engine uses dirty engine oil to control cams hydraulically thru small screens and passages . Get her clean and keep it that way . There is more but this is a start . You will notice misfires like to show up around 45 -50 after engine rpm drops and climbing a hill , Engine lugging at those points

Cstrickland33

That hard part is that I cleared the code because I didn't know what I was doing and in my state of panic that what I decided to do. I won't be able to reproduce the engine light unless I drive over an hour away as of right now. After talking with a mechanic friend he told me it sounded like it was the coil and was only acting funny whenever the coil was hot. Does this sound right??

Cstrickland33

Again? These are not factory plugs, so I should do them all again??

techrep

iTrader: (1)

F150Torqued

^^^^^^^^^^^ X 2 to the 10th power.

You might also benefit from my experience with a 'pick 5.4l' detailed here. It is the kind of meticulous detail no 'normal' tune-up mechanic or shop would go to.

https://www.f150forum.com/f4/5-4l-3v...6/#post3930018

qdeezie

To the OP - This right here is definitely a step that should not be ignored. I used harbor freight brushes and carb cleaner (light sprays as to not flood the piston) and brake cleaner to clean the brush each time I pulled it out (held it over a bucket and sprayed it clean) until it came out clean. Some of my plug threads were extremely gritty.

Another thing regarding removal of spark plugs. On Autolite's site, they have really good instructions on how to remove plugs without breakage. I did it with amazing success. Not one plug snapped.

I also made a post outlining what I did. https://www.f150forum.com/f4/autolit...esults-430305/

redfishtd

What kind did you use specifically .Best to use sp546 ,515's were going bad out of the box . . No one will do them as good as the owner if he learns and takes his time . Yes that carbon around the plug tip breaks plugs going in and out, clean it out with carb cleaner ,the way it was in your first 60k miles . Use a torque wrench , and yes it helps if you pull pcm and bracket off to get to no 3 and 4 .. And yes you need to have changed out the boots and springs , but only on the ones you don't want misfires on .
Misfires ruin cats, so get on it ,they are expensive.
We need to eliminate plugs and boots so you may move on to injector diagnostics . .