A little lube, a little more careful ratcheting, and the rest of the plug came out. The plug had actually snapped in half; the porcelain snapped at the top of the metal. Turns out either myself or my friend overtightened them, as the topmost two threads were completely mashed.

Fortunately, I didn't throw away my old plugs (as they turned out to be long-life platinums with at least 10,000 miles left in them). I grabbed one and plugged the hole.

She'* still running a bit rough, but with five copper plugs, one platinum plug, and worn-out wires, I suppose I couldn't ask for more. Obviously looking at doing a full tune-up and oil change this weekend.

ouch, I wouldn't drive like that. Sounds like asking for a chipped piston or something along those lines.

Really? Yikes.

What would cause a piston to chip? The fact that one spark plug may be stronger or weaker than the others?

If the car is running rough, possibly misfiring, I would not think it a good idea to be driving it. Especially since spark plugs can be purchased almost anywhere fairly cheaply. Why take the chance?

Lets talk overall torque...15LBS no more!! (with anti-seeze) you should be fine..3/8" torque wrenches were made for drainplugs and spark plugs...Yet, before I used a 3/8" torque wrench on spark plugs, on a L36 I snapped spark plug torqueing it...best of luck getting the old plug out....a machine shop should be able to get the old plug out...

Good point. My paychecks are sporadic, so that'* why there aren't new plugs and wires under my hood right now.

I can catch a ride to work tomorrow, but if I need to take my car in an emergency (i.e., not a beer run), would it be safer for the piston if I unplug cylinder 3'* spark and fuel injector wires again?

Chipped piston.



This comes from predetonation. The odd plug is bad news on a supercharged engine. Autolite copper plugs are about $1.50 each.

If you drive normal, you should be OK, just stay off the gas. nice and easy.

As for torquing plugs. I have never used a torque wrench on spark plugs. Antisieze, turn in by hand, then 1/16th of a turn, that'* 1/16th turn. Just enough to compress the seal.

I have become a fan of torqueing everything due to my boss who needs everything to be torqued to OE spec.

Congrats on getting the plug out.

Did you happen to get a picture of the remnants? I'm interested on how the tip looked, mashed, beated or hit?