Thermagasket

[irebroff]

I am from Germany and read this thread close all time. Sorry, my English is not very well, but I hope you will understand it.

Can it be that cooling system is not the problem....

If a spark plug is not 100% perfekt, your engine is not missing, but overheating!

The mixture gas-air is not right, whats about mpg ? Do you think your cadillac is very economical? Then I would suggest the mistake is not in cooling system or head gasket.

A head gasket problem is in flat region with high rpms the same as in a mountain drive. I live in Bavaria and we have high moutains

I would check these:

Air Filter
Spark plugs
wiring
ignition coils
fuel pressure
other brand of gas

[rfishing]

Problem has gotten worst, and overflow occurs now at high speeds / steep slopes, ie; under stress, and now is happening when engine temp was below 216. What can cause pressure to build up in cooling system enough to relief the pressure cap below 216 degrees last time, lost a pint of coolant? If the items you listed were suspect, correct me if I am wrong, but the temp would shoot up and then coolant would overflow. My situation now, is coolant overflow before temp get high.

By the way, this car has 97,000 miles on it, but was major tuned at 67,000 miles. Including new wires.

[Ranger]

Originally Posted by rfishing

Problem has gotten worst, and overflow occurs now at high speeds / steep slopes, ie; under stress, and now is happening when engine temp was below 216. What can cause pressure to build up in cooling system enough to relief the pressure cap below 216 degrees last time, lost a pint of coolant?

When a head gasket is breeched, exhaust gasses are pumped into the cooling system, thereby pressurizing the system well over the 15 psi cap pressure, thus causing the overflow.

[rfishing]

By the way,

I do want to thank everyone for all the support. Throughout this ordeal, I have had a lot of messages obviously, and have learned a tremendous amount about cooling systems. Again, if I decide to pursue a do it yourself repair on this vehicle, or have any further questions, I will start a new topic. The Thermagasket topic is closed, see a few messages back for summary of results.

If anyone has other advice, please send me a private message, do not post in this message.