This is the first time I ever done this, so go easy on me. Anyway, I purchased a used 99' F150 5.4L awhile back, probably had about 125,000 miles on it, and the previous owner never took any care of it. The other day I got a misfire on cylinder 4, so I decided now is the best time to give it a tune up.

Anyway, once I got to cylinder 6, I pulled the cop, and found what appears to be an o ring(on the spring) and a red gasket of some sort? Also, the sparkplug was covered in fresh motor oil, is that normal, and any idea what these foreign objects are from?

Btw, the sparkplug next to the red gasket in the pic was from cylinder 4, should I be concerned about all the old oil on that plug as well?
http://postimg.org/image/7nk3z0gwf/

 

the spring is from a coil and that square red deal is a gasket that goes in the connector to the coil. The oil is likly from someone adding oil to the engine clumsy spiller. Clean the plug well out as good as you can an dont spill oil in there..

 

Where was that red silicon(probably) gasket at? Was it wrapped around anything or just hanging out in the chamber lol.

Yea, what jethat said. Look at coil harness connectors, see if ones missing. You can see the gasket looking into the connecter. IF you have any left lol.

 

Wow, you see how wore those plugs are! Probably factory lol. Yea, those plugs have been discontinued quite awhile ago. They also promote cross threading big time. You won't find those plugs anywhere, - thankfully. All you have to do is over torque those just a little bit and they'll run up high enough (maybe 1/16) on the shank to screw up your chamber threads.

Did you blow the cambers out with compressed air before removing the plugs ? If not you better vacuum out the cylinders.

Black O-ring, - Not sure, but it definitely shouldn't be there. I'm kinduh wondering that whoever owned the truck before you tried sealing a leaky plug chamber, - ie a compression leak.

Clean everything up the best you can and keep an eye on #6. If it fills with oil again, -head gasket F'ed.

Personally I'd compression test it while doing the plugs, - if you can.

 

BTW, - New plugs will seal allot better than that design. They're threaded all the way up the shank. just don't go crazy on torque, 28' lbs, that's it.

 

ONLY use "MOTORCRAFT" Plugs, - nothing else.

 

Yeah, the red gasket wasn't wrapped around anything, just sitting in between the coil and plug; It probably slipped off the connector when I pulled the coil, and of course, I freaked when I seen it, the o ring, and the fresh oil.

I did blow out the chambers with compressed air before pulling the plugs, but all that old oil that was caked on the boot and plugs do got me worried, i'm hoping none of it fell down into the head. Also, I did go motorcraft on the new plugs, and I torqued them all down to 30lbs. I'm slightly worried about cylinder 4, with the use of a swivel socket and all the extensions, I didn't know if that would alter the torque reading.

 

Ya the red Oring is part of a "weather pack" connector, you definetly want to reinstall that in the connector.

The black could have been a sliver from the coil boot? Maybe?

As for torque the swivels will lower the effective torque as well as extensions. They make calculators to figure out how much you're loosing through what different adapters. Even a deep well socket can read differently from a standard height socket

 

If I were you, I'd replace the coils too. At least replace the boots.

 

Looks like it was running alright tho. Wonder what the gap is on those lol.




Looks like an 1/8" lol.

 

I probably should have did the coils, but I did replace the boots when I put my new plugs in.

 

Well if the misfire is gone, good enough for now! Nice work, I know the job can be intimidating the first time.