how likely do i have a head gasket failure/cracked head?

[tootsie]

1997 4runner with 200k miles was sitting for a couple weeks while I was away, and when I ran it again upon coming back, sweet white smoke started billowing from the tail pipe. before i went away on my trip, i've been driving the car everyday with no problems, although I did suspect something cause the exhaust smelled sweet only when i started it in the morning, but the smell would go away after driving it for a bit. I did a block test that also came out negative. theres no overheating and no engine codes, although I did have a misfire code on cylinder 3 which went away after replacing spark plugs a few months ago (the spark plug in cyl 3 was seized, and we rethreaded the sparkplug hole).

my question is could this be anything else except a blown head gasket/cracked head?

 

[AuSeeker]

It's sound like the most likely possibility, when you run it and then park it overnight coolant leaks past the head gasket and into the cylinder, onxe you start it the coolant burns off, the next test would be to pull the plug and insert a bore scope/snake camera into the suspect cylinder and see if there's coolant on top of the piston.

If you find it is the head gasket and you can't afford to replace the gaskets you may want to try one of the head gasket leak sealer products.