Head gasket........

[blck94boosted]

So for the past two weeks or so my car has been smoking white, and black. Smokes while driving, idleing. Now I have 120 compression in three and four cylinders,. but in one and two I have 0 compression. Any ideas, not the normal symptoms of blown HG, no oil in coolent, not overheating, no lack of coolent.

[yokotabrat]

The headgasket could have blown right between cylinders 1 and 2. I just had this happen a little while ago with cylinders 3 and 4. If you have a way to do a leak down test, that would tell you for sure.

[drcustom]

Seems like a small chance, but I wonder if the blown cylinder happened before/at the same time as the HG...

I'm thinking the oil and coolant would be under more pressure than a dead cylinder, so those things could be leaking into the cylinder and burning without being pushed back somewhere else...seems unlikely, but just a guess.

Maybe you ate a valve and it cracked the head or something like that...but I'd guess you'd have some idea that that happened.