I just blew a spark plug but after putting it back in, the car runs fine. Do I need to do anything else?

Dear Car Talk

Dear Car Talk | May 01, 1997

Dear Tom and Ray:

I was driving home from a friend's house and was on my way up a hill when
I stopped at a Stop sign. After restarting and letting the clutch out on
my 1986 Ford Escort GT with 120,000 miles on it, the peace was shattered
by the sound of my No.2 spark plug attempting to be the first such
automotive part to land on the surface of the moon. It just blew right out
of the engine with an incredibly loud noise. I found the plug lodged in
the insulation on the underside of my hood. So I removed the fuzz, screwed
the plug back into the block, and reattached the wire. After that, the car
ran fine.

Do I need to do anything else? And is this a sign that the end is near for
this engine, or did my mechanic just forget to tighten this plug during my
last tune-up? -- Randy

TOM: Isn't it amazing how much power spark plugs have when they shoot out
of a cylinder like that? I've got about six bumps on my head from similar
spark-plug "launchings."

RAY: You mean the spark plugs blew out and hit you right in the head?

TOM: No, in each case, I was napping on the creeper underneath some other
car, and the noise jolted me awake and caused me to bump my head on the

RAY: Your mechanic just forgot to tighten the plug, Randy. He screwed it
in with his fingers and forgot to tighten it the rest of the way with the
ratchet wrench. And as you drove around, the "explosions" in that cylinder
slowly unscrewed the plug the rest of the way, until finally it went
kablooey. This is just one good reason why cars have a device called "the

TOM: And as long as the plug wasn't damaged, you should be able to just
screw it back in and keep driving. But there is one other thing you should
do: Check the other plugs to make sure they're tight.

RAY: There are torque (tightness) specifications for the plugs, and to be
sure this doesn't happen again, you want to be sure all of your plugs are
tightened to those specs. And always remember to drive with the hood

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