Ejected Spark Plug

[Mr95Gl]

What I thought was an exhaust leak, COP failure, and bad VC gasket happening all at once turned out to be the #5 spark plug exiting the head. Is this a common occurence (it happened on my friend's 98)? Do I need to start looking for a new head?

 

[jthod]

It's usually a problem with the 5.4, 4.6, etc...

Not a problem I've heard much of on the SHO's.

 

[1993MTXSHO]

It's usually a problem with the 5.4, 4.6, etc...

Not a problem I've heard much of on the SHO's.

yeah, I think it's more common in the 5.4's too because of how the engine sits in the engine bay. I believe it is the cowl seal that allows water to drip on the engine in the F-150/Expedition's. Anyway the reason for it usually is somehow water leaks in the engine bay and sits in a plug well, it corrodes the well and threads and then eventually it just shoots the plug out of he head.

Call Ford, IIRC they actually have a recall kit to fix the stripped out plug well for the modular engines, maybe they have one for your car, or maybe the mod motor kit will work for you as well.

 

[SHO U UP]

Yeah, thats the first I heard on an SHO doing that. Ford corrected the problem with the 5.4s by doing 8 threads in the heads as opposed to the orginal 4 threads.

 

[nothingtoseehere]

Correction, the 5.4 2 valve, the 5.4 3 v has no plug ejection issues.

Not overly common on the SHO 3.4, but not unheard of either.

 

[Pro*banshee]

Correction, the 5.4 2 valve, the 5.4 3 v has no plug ejection issues.

Not overly common on the SHO 3.4, but not unheard of either.

You're right, it is only the 2 valves

My buddy's mom has an expedition that shot out #3 while she was just cruising down the road one day; they had to replace the whole head though since the plug threads were corroded/stripped

 

[Mr95Gl]

Thanks for the responses. My next question is, what was cause it to happen? The plugs were replaced about 8K miles ago. The only issue I've had was having a coil fail on that same exact cylinder. Guess it's time for a rethread kit. . . . . .

 

[Racer X]

Is the car still at work or did you get it home last night?

You have either the greatest luck in the world, or the worst... there's no in between with you!

Let me know what you need Fran, you know the deal.

 

[Mr95Gl]

Is the car still at work or did you get it home last night?
Let me know what you need Fran, you know the deal.

After trying to find a shop that would just take a look at it, and then overcoming an hour of Goo Goo Gaa Gaa, I finally decided to tow it home after being told what the issue was. I'll definitely let you know what's going on.

You have either the greatest luck in the world, or the worst... there's no in between with you!

Yeah man, no kidding. I've been long overdue for a SHO catastrophe though.

 

[Mr Anonymous]

99% of the time, this is due to someone cross-threading the plug on installation. That's why I always tell people to thread the plugs in by hand and only use the ratchet to snug them. This is how any plug going into an aluminum head should be installed; but sadly not everyone does it this way.

You can try putting in an insert. I've done a number of them, including one in a rest area parking lot on the Thruway in Syracuse on the way to the Kalamazoo convention. The kit is about $60 at NAPA, and you'll also want to buy a big tube of dielectric grease to slather on the tap so the aluminum shavings stick to it and don't fall into the cylinder. I usually back out and clean off the tap and re-apply the grease every 720 degrees.

You'll also need a full-threaded spark plug (a la AGSF-style, not AWSF) because the plugs with the shoulder won't work with an insert.

Chances are you blew out the plug well o-ring as well so you'll want to pull the valve cover to check.

 

[LJRuddy]

I had this happen to my Mustang GT a few months ago. For me, I had 3 ejected plugs and during tear down of the intake, I discovered a 4th plug getting ready to pop out as well.

I used the Timesert method of repair.

I was able to do 4 plugs in about 2 hours (took my time as I didn't feel like putting a new new set of PI heads on) and I was on my way with a fully functioning V8. The repair was quick, easy, and painless for both myself and my wallet.

For what its worth, both NAPA and O'Reilly's sell a similar repair that is much cheaper (8 bucks a plug minus the 25ish bucks for the necessary tools) and does the same thing. :wave:

 

[grabbor]

i also had mine do that..i did like Mr Anonymous said to do..i bought a spark plug thread repair kit at the local parts store for abour $30..it was a solid insert and will work with fatcory plugs..

 

[Pro*banshee]

ALSO mr Anonymous

Don't forget that if you stop at just hand tightening with the socket and don't snug them they do work themselves out and the threads strip when there are only one or two still holding


These are the best to recover from since you still have the bottom two threads for the coil to grab onto when you replace them with a new one

 

[Mr95Gl]

99% of the time, this is due to someone cross-threading the plug on installation. That's why I always tell people to thread the plugs in by hand and only use the ratchet to snug them. This is how any plug going into an aluminum head should be installed; but sadly not everyone does it this way.

Makes sense. All 8 plugs were replaced right before I picked up the car. Guess it was only a matter of time. Now I'm wondering if I should remove, and re-install the other 7?

You can try putting in an insert. I've done a number of them, including one in a rest area parking lot on the Thruway in Syracuse on the way to the Kalamazoo convention. The kit is about $60 at NAPA, and you'll also want to buy a big tube of dielectric grease to slather on the tap so the aluminum shavings stick to it and don't fall into the cylinder. I usually back out and clean off the tap and re-apply the grease every 720 degrees.

You'll also need a full-threaded spark plug (a la AGSF-style, not AWSF) because the plugs with the shoulder won't work with an insert.

Chances are you blew out the plug well o-ring as well so you'll want to pull the valve cover to check.

Ah great, thanks for the info!

 

[xll_VIPER_llx]

My 92 explorer did this with 2 of my plugs and i used a tap to extract the leftover metal thread from the plug no problem....only part that sucked was i was in the middle of no where in farm country when it blew,,,,i'll never forget that popping sound all the way home again!

 

[Mr Anonymous]

ALSO mr Anonymous

Don't forget that if you stop at just hand tightening with the socket and don't snug them they do work themselves out and the threads strip when there are only one or two still holding


These are the best to recover from since you still have the bottom two threads for the coil to grab onto when you replace them with a new one

That's what the other 1% is. That's also what a back-tap is for.

Makes sense. All 8 plugs were replaced right before I picked up the car. Guess it was only a matter of time. Now I'm wondering if I should remove, and re-install the other 7?

Yes, I would strongly recommend R&R'ing the rest just to make sure.

 

[Mr95Gl]

Nevermind .. . . . . . .

 

[Mr95Gl]

Turns out the whole front bank was finger loose. I'll be pulling the intake tomorrow to check on the rear.

 

[Ian Macoomb]

While it's not all that common, Kirk managed to diagnose my car by listening to it over a cell phone. My car was the one that Chris fixed at a rest stop on I-90.