one of his sparkplugs on his 87 accord fell out, he says he drove 50 miles like that, with an open hole spraying gas all over the engine, ting smells like a lawnmower now. what kind of damage will that do?

Lets hope there wasn't a good enough mixture for the sparkplug wire to spark and ignite the engine bay. That wouldn't be a bonus.

How does a spark plug "fall out"?

i actually had to tighten my spark plugs on the bonneville not long ago, when i changed them, i snugged em down just like i always have...i have no idea how it happens

he says the sparkplug fell out because the piston went, could that happen, or could driving with an open cylinder blow the piston?

mmm..I ran with 3 plugs barely hanging on (like 1/4 turn in) for a while. ran like *** but no probs once tightened. that one piston probably just turned into a pump and if it didn't start a fire I wouldn't worry about it.

I'd have to agree. If the car is in bad enough shape that sparkplugs just "fall out", then misfiring for 50 miles won't really make any difference.

i meant would the plug coming out be a result of the blown piston, r would driving without a sparkplug blow the piston?

If it pre-ignited or detonated hard enough to blow a sparkplug out you'd probably see oil spray out of the hole. And no, I can't see how just having the plug pulled would burn a piston. Even if it did ignite the fumes a 0.5:1 compression ratio (or whatever) would result in minimal pressure.

I had a friend with an old accord (I think) that had this happen. It was before I cared much about cars so I never found out why. I do know he got it fixed and drove it for years afterwards though.

Explosions are cool.