Worst case scenario...my engine is DONE! It has 180 k on it and my car just broke down on the freeway...I haven't had the chance to have it fully diagnosed. I was told by a shop here in Fresno that the labor to remove and replace this engine is a mind staggering 18 HOURS!!! DOES ANYBODY HAVE ANY INFO REGARDING THIS? THANKS!

Well, to be honest, I would first get it fully diagnosed and find out what happened and what exactly are your options. There are still to many questions to answer before anyone can give you any real usable advice. Is the block cracked or did you just drop a cylinder? Did you timing belt let go and maybe you just crunched up your valves? Did you crack the head? Just saying your engine is toast isn't really giving anyone anything to go by. What exactly is broken about the motor? And don't be freakin out. Theres alot of things that sound like a huge big deal, but really aren't as bad as you might think.

What is the BEST method to diagnose the head gasket? Compression test...Chemical test or Infrared test...Pressure test?
I've been told that chemical and infrared tests are the best way to diagnose whether or not the head gasket is blown or if there is internal issues with the engine!

Thank you!

A compression test will only tell you there is a leak, but a chemical test will tell you there's a leak and where the leak is.