My truck has 134,000 miles on it and I put champion 1 piece plugs in at around 100,000 miles. My check engine recently came on so i pulled the code P0300-random misfire. I figured maybe it was the coils since ive never replaced them but didn't want to replace all of them. I took it to ford for a diagnostic, they said it needed a fuel injector cleaning and that it needed motorcraft plugs put back in it. I told them not a chance. They also tested the coils and said they were fine. How long are champion plugs supposed to last?

 

I would definately have the injectors cleaned or try running some injector cleaner in the gas for a couple tanks. Had a misfire code pop up on my folks Oldsmobile and it was a dirty injector and not coils or plugs. There are a lot of threads on this forum about Motorcraft vs Champion. Personally I only stick with motorcraft engine management parts, and have heard that the champions do NOT last as long as the motorcrafts in the 5.4 engines. There was a thread not long ago where others were debating about the plugs. Just my .02!

 

Dude out the sooooooooooooo many tune ups i have done on Fords I very much recomend using Motorcraft plugs. When i get a vehicle with what you are describing my diagnosis goes like this.
Verify if the engine has a miss.
check codes... p0300 "pretty non discript"
monitor power balance, load the engine to find the miss if it shows up act accordingly, if not able to catch the miss, then check "mode 6" it is software that logs each cylinder miss.
If I get a cylinder that is tagged then i pull that coil and look to see what up.
More often than not I find either the boot is hard and not sealing around the porcelin or the seal around the boot has failed and the hole is full of water ((most common)) If you replace 1 boot then replace them all espesially if you are using champion plugs, they dont have the ridges like the boot design mandates.
If all of that looks good and I cant find the smoking gun then I check the vehicles software vs.
One more thing I have seen other non ignition things set that code, like a alternator with a diode problem, a transmission that is starting to have issues, and one of the most that shows up a lot is the tubes to the pcv valve system, like the elbos that are made of rubber that cave in and suck unmetered air (you can see them if they are bad. Good luck

 

The dealership said it was missing on cylinders 1,2,and 8. They supposedly checked the coils and said they were fine but ya, I will look at the boots. I also took the tune off and put it back to stock, The cel hasnt came back on but you can definately here the miss at idle. Also if I give it alot of gas while driving it smells funny.

 

People have had this problem with the champions after about 30-40k on them. For some reason these trucks just don't like the one piece plugs very much. Don't start changing all the coils and injectors just yet. Replace the plugs with motorcraft or another quality 2 piece plug. I am betting it clears up your issue.

 

I have been doing a lot of work on these 3V 5.4's, I would suspect you have a plug problem, the boots are quite durable and I am yet to see one with problems. I do know that the plug type that these motors call for have a lot of problems no matter what manufacture you get them from. I would start by getting OEM Motorcraft plugs put in it. you shold be able to pull those plugs yourself if they have not been in there long. Now with that said, it is also common to have bad motorcraft plugs but the odds are low. If you change plugs and have one bad one, your code will look something like a P0303 or P0316, this will isolate the bad plug by it's firing number.

 

I replaced the three plugs in the cylinders that ford said were misfiring with the autolite plugs and the plug in cylinder 1 was missing the electrode when I pulled it out. I know I need to replace all of them but dont have the money right now, any who I replaced the three and it still misfires pretty bad when I started it back up.

 

Don't let it go too long without replacing the rest of the plugs, I would also stick with Motorcraft, they seem to work the best in these motors.

 

So the only real fix to this sparkplug problem is to swap in a 5.4 from an '08 F150? Would one swap in relatively easy?

 

There's really no need for that. If you do break off the bottom of the 2 piece plug it's not a disaster. My 05 has 273,000 on it and i have only changed plugs twice and it runs great. Out of 2 changes i have only broken one plug. Bought the removal tool for 80 bucks that i later found on ebay for 35 and getting it out was a snap. Just take your time and don't panic, don't force, and be patient. That's a lot cheaper than swapping motors unnecessessarily. There is also a TSB on this site that if you follow for plug removal you probably won't even have an issue. Good Luck!

 

69FORD99, if there was an electrode missing from one of the plugs when you pulled them, that could be caused by detonation. If the fuel system is not up to specs, that could cause detonation. In fact fuel starvation is a very common cause for detonation. Given the age of your truck, I would definately check the fuel system out. I'd also have a look in that cylinder for any pieces of the plug with a bore scope.

 

When I changed out the plugs at 100,000 I took my time followed the tsb and broke 6 out of 8. It was a real pain that no one should have to deal with. Maybe im old fashioned but like the older motors that took 20-30 mins to replace plugs. could the reason for the broken electrode be from a couple times when I floored it from a stop with the low fuel light on the truck did cut out when i did that.

 

It's possible. Platinum plugs are very fragile when it comes to detonation. That's why it's recommended to use resistor plugs for supercharged applications. I prefer to use resistor plugs for towing as well as general use. They do require changing more frequently, but are not as fragile as a platinum plug. There might be a resistor plug for our trucks, but off the top of my head I don't know who offers them. I do know that my brother-in-law lost an electrode on #3 cylinder while trailering his son's Ranger from Indianapolis to South Bend (125 miles) last winter and he wound up ruining the engine because the broken piece scored the cylinder. After that, it smoked like a 50's Evinrude. He has an 02 4.6L 2 valve engine.