Head Gasket vs. Bad Valve vs. Intake Manifold...???
I bought a 2000 Blazer LS in May with about 163,000 miles on it (now has about 166,000), 2 DR, 4WD, 5 speed.
One hot day in June while driving home from work the engine stared missing. The temperature gauge was normal and everything was running fine, I just gently downshifted going up a hill on the highway, there was a little hiccup, and kazaam; misfire.
I took the Blazer to the mechanic that had done some work on my fiance's S-10, he hooked up to it and read that the number 6 cylinder was misfiring. He recommended that I do a tune up. Six new spark plugs, a wireset, and a distributor cap and rotor later, and she's still misfiring.
Then a friend of mine was looking over it and noticed that my coolant had oil in it. He voted that the head gasket was blown. His landlord (who is a mechanic and owns his own garage) took a look at it and told me that there was 0 compression coming from cylinder number 6. He voted either a bad valve or a blown head gasket.
I drove the Blazer down to my dad's place so he could look at it, and he talked to his best friend (another mechanic who owns his own shop). His vote was either a blown head gasket or the intake manifold.
I'm not sure what to do. i can't afford a new engine, and can't get a reliable answer on what the problem might be from anyone. Any advice contributed would be greatly appreciated.
Again, laundry list of symptoms are:
Miss on #6 cylinder
0 compression on #6 cylinder
Oil in the Coolant (not vice versa)
Unstable idle ( vehicle revs up to 2 or 3k RPM and back down to idle speed)
Never overheated in the time that I have owned it, even after the misfire occurred.
Thanks for the help folks, I've only gotten to enjoy this vehicle for a short time since I bought it, and with winter coming I'd really like to get her back on the road and enjoy her.