I took the oil cap this morning and no residue. Looks very clean.

I did have a little pressure when I took the radiator cap off, but not much.

I will try the t-stat this weekend.

 

I've been having the same issue and I changed my t-stat and rad cap but it didn't help. I also checked my old t-stat and it was fine so my issue looks to be the HG. Bummer

 

I changed everything in my cooling system including the radiator before biting the bullet and deciding it was my head gasket. The reason I was reluctant to do the head gasket was that it passed a lithium and pressure test.

But after exhausting all other avenues I pulled the head off and sure enough, it was the head gasket.

 

Well in a way its kind of good news that you guys are telling me this. I might as well save the $$$ changing everything in my coolant system and just go right to the HG.

The t stat will be easy to get to while I am there. I like to go OEM especially with t-stats, but has anyone had any good luck with any of the lower temp t-stats. I wonder of their reliability though.

Anybody know a rough idea on how much a HG will cost to get done & a new tune. I am still in the process of drywalling my garage and we are still in the mudding and sanding phase. I still have to prime & paint and put up my cabinets. This will take me a couple of weeks still so I really do not my car to be down for that long. Id rather pay someone to get it done so I can start drivinng it soon. Nice weather has been somewhat of a rarity here in Chicago lately, so I want to take advantage of every nice day we get.

Thanks again for all the help guys.

Joshua

 

SlowS2k suggested a test that will confirm a blown head gasket.

Run the car up to temp, get on the boost, then shut down and pull the plugs.

Hold a mirror over the plug tubes and if you see condensation you have blown a head gasket.

Personally I'd stick with the OEM thermostat. With a working system it keeps the car in operating range and is more than adequate. It also have the bleed hole which some aftermarkets omit.

As to costs, couldn't say. Gaskets here range from $AUD180 (oem) to $AUD500 (3mm Inline Pro landed). Work tooks us home mechanics about 12 hours.

 

For the heck of it, I did a pressure test on my coolant system and it held the pressure fine. I took out the spark plugs to see if I got any pressure leaking from the HG. But nothing, It held pressure fine. I had it up to 15psi. Should have I gone to a higher pressure?

AusS2000,

Didnt you say you pressure tested your coolant system as well, checked out fine but still had a bad HG?

 

Yep.

15psi is one thingbut holding combustion gas in a forced induction car is another thing altogether.

 

I figured that. I am gonna try to the mirror test.

 

Just wanted to give everyone an update on my car.

I eventually took the car into profunction to get my car checked. It turns out that the cometic HG did fail.

The head was tested and there was no warpage and the valves were fine too. They put a new oem HG on and while it was off, they threw on a slightly used header for me that they had lying around.

Got a full re-tune on the dyno and I was very impressed with the numbers. 395.5whp. I did not expect to get these kind of numbers with the oem HG, header and re-tune. I am very happy with the car and in a way I am kind of glad the cometic HG failed. It turned out better.

I was recommended to profunction by a couple of members here and now I know why. Special thanks to Mikey and the guys at Profunction.

 

How much did you pay to have your HG replaced?