2manyprojects

hey i have an 05 civic vp. my question is a little complex so I will try to make it as clear as possible. my engine is the 1.7 non vtec while i was sitting at a stop light it started making a kind of bearing type grinding sound shortly after the checkengine light started flashing so i parked it. when I checked for codes I had misfire codes on all 4 cyl. took the engine apart and best i can tell the piston on cyl#1 made contact with the spark plug forcing it through the head in to the coil pack. what could have caused this. ps the onnecting od nuts were tight. thanks for the help

01hxcivic

check the timing belt

BlueEM2

iTrader: (1)

It's not likely the piston hit the spark plug unless you either have the wrong spark plug, or something is horribly wrong with the engine. I think you may have had some detonation on the plug and it was installed loose so it looks like its damaged and pushed out... I'd replace the plug and see what happens.

2manyprojects

I checked the timing belt, that was my initial thought. However, the top of the spark plug is flattened, and the coil pack is destroyed. Also I noticed some markings on the piston, as well as some contact points on the head between the intake valves. the ground electrode is also missing from the spark plug.

BlueEM2

iTrader: (1)

The only thing that could have really happened is if you spun a main bearing which allowed to piston to move higher up in the cylinder wall to come in contact with the spark plug. This is not likely though, post some pictures.

sdaidoji

iTrader: (1)

?!? That is really odd.
And no, timing belt would cause problems to the valves, not the spark plugs.
So or you have really high pistons head, or your spark plugs are too deep in the chamber, or piston went too high in the chamber for some reason (as Tbohar mentioned).
If the latter is true, how does your valves look like? they could have hit the piston as wel... usually thye would before the plugs, i guess if timing is right.