I think my timing belt went south causing my pistons to go up into my #1 and #2 spark plugs, what do you guys think?


[Modified by Prelussion, 2:16 AM 2/22/2002]

 

If I am not mistaking, your valves will hit way before the piston hits the sparkplug

 

I can say with almost 100% certainty that the piston didn't hit the plug.

 

yeah, that explains the ticking noise, and then what would cause the spark plugs to do that? and again when they were changed and the motor was restarted?

 

Only thing that could cause that, I think, would be some kind of solid debris flying around in the combustion chamber.

 

That happened to me on 4 of 6 plugs on my 91 300ZXTT. Except 2 of them were busted up quite a bit as well. When I put in the new plugs, and restarted that POS (yes it is) I heard the pieces banging around in the cylinders for ~~2 minutes at idle. Then the went out the exhaust (I assume) and it was cool. Do not know what cause it, but I think something was broken in there or went in the intake.

 

maybe heat failure, it may have curled up on its own during a very lean cycle, now it looks fuel fouled from not igniting the mixture - just a thought.

 

well i do hear a ticking, and when i changed the flugs i restarted it and let it run for a matter of seconds before i took the new set out and found that they were in the same condition. Also the guy w/ the 300zx....i hope you took off the head and had a look.

 

A broken timing belt will never, never cause the piston to hit the spark plug.

Here's the thing: the spark plug doesn't move up and down like the valves do. A broken timing belt causes some valves to stay open, which is why they can get hit by the piston.

The travel that the piston goes through is dictated by the dimensions of the crankshaft and connecting rod, and these don't change.

 

Take off the head or use a fibre optic camera to look in the cylinders.

 

Some MAJOR detonation could possibly cause the gap to close, but that seems as though something actually hit it...

 

Well, the end of the plug shows something has hit it. Causing some dents.

 

Well, i finally had time to look at it more, and the Dealership screwed me over. they said the plugs they put in fugged up too....Well i pulled the plugs they put in after they took my Densos out, and they're fine. the cars runs pretty ok....but it makes a noise which seems like a misfire sometimes, and it also makes a rattling noise that is head from around my intake manifold of throttle body. Also it does continue to bog minorly at different RPMs, it seems that when it makes the rattinling noise it bogs. but the thing is it doesn't always happen at a certain RPM or anything....It's random.

 

Did they pull the head, use a camera, or just replace the plugs? I think I would raise hell if I were you.