Ouch. Arent spark plug electrodes ceramic ?? If so then it can cause some serious damage. I will agree with apme123 to start looking at new motors or at least some used longblocks..... or maybe an ls1 with ls3 head hahaha. Sorry man and best of luck

 

It was the ground electrode, but that's a (fairly) hard metal. It's making some hellacious noise now. Have a lead on a 04-05 motor for him that a buddy of mine has. Sad day for sure, but it is what it is.

 

The broken electrode probably caused the misfire. But what broke the electrode? Maybe severe detonation?

Dealer says bent rod? I'm no expert, but how much noise would a bent rod create? If they think its bottom end, wouldn't rod knock be a much more likely culprit?

I would think with a mechanics stethescope you'd easily be able to isolate if its tip or bottom end.

But if now its so making much more noise, its probably all moot, does sound like engine is toast.

But if its just bearings, and cylinder walls are still good, it should be feasible to rebuild, right?

 

I agree, that I highly doubt it was a bent rod.

The engine is definitely toast. Even IF the block was good and it was JUST rod knock, you're still looking at a new crank, rod, bearings, gasket set, labor etc. And 99% of the time when there's rod knock, you have scored cylinder walls as well.

I doubt the walls are trashed from the knock since it just started, I'm betting 100% they were trashed by the electrode which sounds like it could still be in there. Not really worth investigating further for now with how much it'd cost to rebuild vs. how much he's going to get a much lower milage AP2 motor for.