My Motor Ate My Spark Plug

My 04 Tocoma 2.7l ate my spark plug & burnt up the coil. I can now look directly at the piston top through the plug hole. How much trouble am I in for? Will I need to pull the head off or can I remove the rest of the spark plug from above? Motor has 237K miles, Is it time for some new parts anyway?

 

Chew some bubble gum, put it on a stick and fish for the parts.

 

wait wait..... what happened?

first off if its an 04 thats first gen.

Second, did the plug back itself out? did something fall down in the cylinder?

 

Did the plug strip the threads? How the hell does a plug just fall out? Or in?

 

I've seen cases of this. Ford had a huge 4.6 problem a few years back. Engine would actually blow a plug out of the hole, taking the threads with it. I don't remember the specifics, but I seem to recall it had to do with the plug backing out a bit from vibration, then "foom!" it would be ejected, taking the coil with it. You can helicoil a spark plug hole if that is all that is wrong.

If you look at some past Ford discussions, they had huge problems on removing plugs. The procedure was (1) loosen plug 1/2 turn, (2) pour a bunch of liquid wrench or some other penetrating oil in hole, (3) let it sit for at least 15 minutes; (4) remove plug and hope like hell it does not gall the cylinder head threads and get stuck. So many got stuck and broke off leaving the bottom piece of the plug stuck in the motor, they put together this clever removal kit where you drill out the center of the plug, insert a small "umbrella" through the hole and open it to catch all the metal pieces, then drill out the old plug and helicoil the thread.

The danger you face is that as the plug unscrews, fewer and fewer threads hold it in, until combustion pressure overcomes the thread's ability to hold the plug in. Once those are ripped out, you won't have enough left and if you screw in another plug, won't be long before it gets blown out and now you have zero threads. But a helicoil is magic.

 

That looks like it was loose and you had a leak then it slowing got bigger and bigger till you where burring the boot.

 

Oh, my first time I see this happened to the spark plug. Keep us update.

 

Ive seen that happened in 3.4L with shitty plugs or not properly installed plugs

 

Oh and also check your not buring Oil, you can damage a plug faster to cause this.

 

She ran great & uses no oil or water & the plugs were changed 3 yrs ago with no problems since.

 

That is a plug that has melted the tip and the electrode off, as well as the back side. With the kind of miles you are talking, it would be, in my opinion, a good time to consider pulling the head and rebuilding it, and inspecting the cylinder walls and piston tops for any wear or damage. Looks like there was a lot of heat going on there.

 

eh eff it. Does the motor turn freely?

Throw some new plugs in and a new coil and that 2.7 will go for years more.

 

the Fords that spit plugs were the early 5.4s. Biggest piece of shit ever designed. Heads only had 3 turns in the threads. I had one that spit one on Xmas eve in the rain.

 

Yes, I have gone through this very procedure with my 2005 Mustang GT. I have the kit in my workbench. The reason for the plug problem was twofold: 1) crappy 2 piece spark plug design (they are BAD!), and 2) Ford didn't put nickel anti-seize compound on the barrel of the plug allowing it to carbon up and get stuck when trying to remove the plug. I broke three out of eight getting them out, and it took me 2 days to do the job. Truly miserable. Good thing I don't have to worry about it again for another 100k miles...

 

Unfortunately, the same applied to the early 6.8l V-10. Only cost about $1 000 to get the passenger side, rear plug repaired/replaced. Put me off Fords for a while!

 

this thread reminded me I have a borescope

going to change my plugs soon (30,000) and will look inside
cylinders while doing it... just because I can...

OP should find a borescope w/mirror and check piston tops and valves

if things are just dented, but piston walls not scored or piston top melted, run it

 

Though my internet plug gapper might not be accurate, looking at the "good" plug in that pic makes me think 3 years was a little too long on those plugs, how many miles in those 3 years?

 

It was actually all the early modular Fords that spit the plugs (early v-10's were especially bad). The later 5.4's (maybe others) did have a problem getting the plugs out.