Cadillac Repair: 93 STS Northstar Heat Cool Overheat Issue, head gasket failure, coolant temp

Question
Hi,
I just bought a 1993 sts (northstar) here are the issues ive been having. When the car is on highway the coolant temp reads between 230-240 according to the computer display. Is this running hot? When I turn on the A/C (hich is very cold) it raises up the temp to 250 area and I get a "Hot Engine Turning Compressor Off" Error message in display. I turn off the AC and the temp goes back down to the 230-240 range and seems to be running fine.

Part 2 Im not getting any heat. I thought maybe the climate control would not let me turn on heat when it was 85+ outside temp...but this morning when it was 70 degrees out, I tried setting the climate control to 90 degrees and still got cold air.

There is no white smoke from exaust, the oil is normal color, the coolant is nice and green with no gas or combustion smells. The engine seems to be very quiet.

I did the code trick and here is what I got....

No PCM
No IPC
COD A050 History
No SIR
NO TCS
S043 Current
s044 History
s060 History
s061 History
s062 History
s067 Current
PCM?

Id appreciate any feedback at all! My last vehical had a blown headgasket and I am really hoping this is not the same problem with different symptoms... we need heat in our car this winter!

Answer
Unfortunately it does sound like you are getting combustion chamber pressure into the coolant passages which will restrict the flow of engine coolant and cause over heating. This YEAR and ENGINE a very very well known for having stripped threads in the engine block allowing head gasket failure.