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Sparkplug blows out of 2003 Expedition. Roadside fix?

Transporting blood to a mountain hospital, at westbound I-70 scenic overlook I am sleeping because I am falling asleep athe wheel.
Woman heading to Orange County, CA drives in wither 2003 Expedition sounding like a sparkplug is missing.
IT IS MISSING! Blown out.
I told her she would have to tow it to a garage capable of boring it out and inserting a helicoil.
Could I have disconnected the fuel injector and she continued on 7 cylinders? Or would the imbalance of no power from that cylinder cause other problems?
Screw in a bolt as a plug?
I suspecthathe sparkplug was over-torqued and the threads in the aluminum head weakened. She did not know if the sparkplugs had been replaced.
Wish that I could have helped.
(Soon I’ll buy a torque-wrench for our Expedition for when I change sparkplugs.)

Unless you happened to have a spare repair kit for spark plug threads a tow is the best alternative. Helicoil is not in the typical toolbox

If the plug was sill there I would have tried to put back in. It may have just turned out and the threads were sill ok.

Wrapping the threads with Teflon tape can sometimes get the plug to hold for a while…But this too is seldom possible by the side of the road…

Sleeping on the job again Robert? Better than crashing…

Sleeping on the job again Robert? Better than crashing....
Yes. They would be unable to tell my blood from that which I am transporting.

Not a job. I’m just a voldumbteer.
At night I drive closer to 50 mph because of deer or elk(?) along I-70.
This morning on the roadwayvere three large bloodstained areas and along the shoulders two dead dear, one dead young fox and a dead raccoon.

Her engine was too hot to do anything but look.

I think you could drive with a spark plug missing for a short “emergency” distance. Keep the speed down to about 55 on the expressway. If you can pull the connector for the fuel injector even better. Basically it is just an air pump with the plug missing and the other 7 cylinders should allow the motor to run.

Instead of replacing the spark plug, maybe you want to get a tire pump that screws into the spark plug hole. Then, if I tire went down, you would always be prepared to reinflate the tire. Of course, your engine would run on just 7 cylinders, but that should be plenty. We used to run these pumps on 4 cylinder tractor engines with one spark plug replaced by the pump.
I haven’t seen one of these pumps for 40 years, so they may not be manufactured any more.

This is a common problem with this era of Triton engines, seeming to affect 5.4s more than 4.6s. It is not a roadside repair. Too much of a pain in the butt, and few normal people have the Triton thread repair kit and a spare ignition coil (the coil breaks when the spark plug blows out) and spark plug with them to attempt a roadside repair like this.

What causes this? Overtightening sparkplugs in the aluminum head?
Another good reason why I never gun thengine. I gradually attain speed.
Certainly can’t allow this to happen on an emergency bloodelivery.
I will buy a torque wrench. Loaned mine out years ago. (Maybe left a a former girlfriend’s house.)

From what I understand, it’s usually cylinders 3 or 4 that are affected and is caused by too shallow a threaded area for the spark plug in the head. I have never seen or heard of this happening to a 3 valve Triton, so you’re probably safe here. You just have to worry about the unique spark plugs in your engine seizing up as they tend to do, as discussed in one of your recent threads.

From reading a previous post on the topic of some Ford Triton motors with issues in changing spark plugs. My take on it is; a design problem. The tip of the spark plug goes into the combustion chamber too much. This means the treads of the plug are exposed to heat, air, fuel, etc. and the threads over time get a build up of carbon.

The heat hardens the carbon to a point where the threads are no longer threads, the grooves are filled in. If you remove the plugs in this state you have to be very careful. If you just twist out the plug as in most cars the filled in grooves simply destroy the treads in the head which is a softer aluminum material. This in effect strips out the treads in the head. Perhaps you get the old plug out, but there isn’t much left of the threads in the head, so the new plug isn’t held in place properly. More time and heat/cooling cycles and the new plug pops out.

Using a torque wrench isn’t going to make a difference in removing the old plugs. Nor, will is make a difference if the head threads are compromised. Apparently you can remove the plugs in these Ford motors but someone who really knows what they are doing makes a big difference. Not a good idea for a DIY job.

Thank you, UT.
Can’t afFORD $320 to change 8 spark plugs. The dealer also charges $40 to extract every plug THEY break.
So will use repeated carbon solvent applications over 24 hours and carefully remove Ford’special. $15.21spark plugs.
I’ll use the torque wrench to intall the new sparkplugs. Apparently I alwayshould have used a torque wrench on sparkplugs and wheelug nuts rather than my hand-tightening.

All this talk about a damaged head when we don’t know that there is any. I have heard that those Ford engines had a problem with the threads tho. Perhaps the plug just screwed out. I know of that happening to at least 2 vehicles in my time.