What is the normal coolant temperature 1997 cadillac deville?

Answer 1

The system can go to 245 or 250 degrees with no problems on a high demand, heavy load situation. It's designed to work that way. With a 15psi pressure cap and 50/50 coolant mixture in the system the system will not boil until 265 degrees. The Northstar engine has a "loss of coolant' limp home mode that will activate automatically long before you get any thing hot enough to damage a head gasket or anything. The loss of coolant limp home mode is so effective that it's been proven time and time again to run the engine for 50 miles at 50 MPH without any coolant in the system without any engine damage. So you (and your engine) are protected even in your worst nightmares of an overheat or something. It will allow you to drive to a safe place even with all the warnings and chimes going off without any risk of damage.

Forget what used to be normal for coolant temps on older cars. The systems are more efficient at cooling running at the higher temps, the engines are happier and are cleaner (for emissions and internally), get better fuel economy and last longer running at the higher temperatures. The cooling fans are only activated at 225 degrees or above so anything below that is considered ice cold by the engineers that designed the system. There is no need to slow down, pull over and idle or do anything out of the ordinary regarding the cooling sytem. Drive it and quit worrying.

Service the cooling system every 5 years or 100K by draining and refilling with fresh 50/50 DexCool/distilled water to keep the corrosion inhibitors in the coolant fresh to prevent any internal corrosion. That's what causes blown head gaskets. Lack of cooling system maintenance over the long haul.