ss_maro00

ok so i was out screwing around in my car ( racing, digs,highway pulls.....etc..)
and i heard a pinging noise from under the hood. after diagnosing, cylinder 2 had a misfire pulled the plug and there was 0 gap. idk wtf happened but i regapped and reinstalled the plug and it purred like a kitten, i thought all was good it was just weird.

Now i went to work and it drove fine there no issues, no studder, nothing. i went to start it to leave work and it just turned over and didn't want to start... then after the third try it fired up. put with a pinging sound like something was bouncing around in the cylinder.. it shuddered and then fell on its face and died.... now it didn't want to start so i left it at work in the bay and left to get it the next day, so the next day it fired up with no hesitation just a miss and popping sound.

i tracked it down to cylinder number 7... pulled the plug and the same thing as cylinder 2. spark plug had absolutely no gap. regapped it and reinstalled it and now it purs I dont know what it is i have never had anything like this happen and idk what is causing this.

At first i though it was the first compression ring had broke the ring land common on ls1s but it is fine on compression with no studder or anything it runs great.
Any ideas would be greatly appreciated as i am lost on it.

Sales3@Texas-Speed

iTrader: (2)

Has this motor been rebuilt, or is this the original stock motor?

conan

iTrader: (5)

DO the plugs look beat up when you remove them, detonation ? Have you done a compression test or had any tuning done lately?

LS6427

iTrader: (2)

I had this same **** happen to my 427ci when I snapped a rod....but mine was because the piston hit it after the rod broke and the piston flew up the cylinder and hit it......

But how the hell did that happen to you? The piston hitting it is the only way I can see the gap crushing down to zero......

anyone have another explanation....?

Sales3@Texas-Speed

iTrader: (2)

I was asking if it was a rebuild and possibly the machine shop decked the block. This would cause the piston to come more out of the cylinder, but how much is real question. In combination with other mismatched parts, anything is possible. Although, its not likely that it a good machine shop would let a motor go without checking this, but there have been instances more strange. Just my $.02

1nasty86

iTrader: (63)

The "pinging" may be particles of your piston breaking off...... my ls2 didn't really make any extra noise after it broke the top ringland off the piston but no.7 spark plug was almost closed shut and beat to hell...

gpr

iTrader: (6)

I have also seen extreme detonation close plug gaps. Very rare but it can happen.

joecar

Loose fragments in cylinder.

ss_maro00

The spark plug had no signs of anything touching. Just gap closed. I first thought it was a ring land but compression tests came back good. I was talking with my instructor at ranken and seems to think somethjng in the intake is breaking apart and finding cylinders on the intake stroke. But it is the stock ls1 engine with no work but egr delete and an ls6 intake. Also no tuning has been done whats so ever. Idk what it could be. Maybe coulda been carbon knock? I dont know

conan

iTrader: (5)

What plugs are you running?

ss_maro00

NGK plugs are being used

Ron_Stoppable

iTrader: (1)

Is your timing off? Maybe retarded?

chrisfrost

iTrader: (8)

If it had anything to do with ignition timing it would be advanced too far that would cause the problems You describe ,,,,,,,,but not very likely as the reluctorwheel and the crank pos sensor are fixed . Although the reluctor can become loose ? My guess would some engine part (ring land) or some foreign object .

Old Geezer

iTrader: (3)

Check the center electrode. I've seen them come loose in the porclean, and drop down onto the grnd side.