View Full Version : cooling system problems

09-15-04, 06:19 PM
i just bought a 97 deville with 71k miles, it's having a cooling system problem.when i first test drove the car it ran fine even on the way back home after i purchased the car which is about 50 miles away from where i bought the car. after about a week of driving the car in town i drove the car down to mobile which is about 60 miles away from where i live and it didn't run hot on the way there but the next morning i left and hit the interstate and about 30 miles into the trip it ran hot on me and a message reading coolant level low read and then idle engine message. The car eventually turned itself off. Even with the car in idle the car would not run hot. At one time it would just run hot whenever i was on the interstate but the temperature would bounce back and forth. i put a new thermostat in it and it continues to run hot. i took it to someone they took out the radiator and took it apart and cleaned it out, the fans are cutting on at 222 deg like the are supposed to and there aren't any leaks from the hoses. the mechanic at the chevrolet dealership told me it may be a blown head gasket and they were not able to find the problem. But the crazy thing they could not find any water in my block or in my oil. The car is not losing power or pressure. After i got it back from the dealership it seems as if the problem has got even worse. Now it doesn't take it 5 or 10 minutes or 3 or 4 miles for the temperature to go from 79 deg to 230. The car will run hot but i won't let it because i just go to work and home after work in it. But out of the 5 days i work in the week 3 of the days the temperature would get to about 199 deg and it would go back down to around 188 or 190. i think it may be my water pump it not fuctioning right or it is slipping. could my water pump cause this to happen. its like the water pump would circulate coolant whenever it wants to. could it also cause my temp to keep boucing back and forth like that. And if it was a blown head gasket would the temp be bouncing back and forth like that.

09-15-04, 06:26 PM
its urgent. could someone reply quick

09-15-04, 08:07 PM
Search the forum for cooling, waterpump,overheat, etc. There are alot of threads on this.
Things to check:waterpump belt condition and idler/tension arm for freedom.
Did the shop install an GM thermostat or a after market item? My 94 Eldo ran 10 to 15 degrees cooler after I installed the factory thermostat,new coolant,waterpump belt,and coolant conditioner stuff [Bars Leak Goldenseal]. Hope this helps.

09-15-04, 10:37 PM
Have you checked the belt and tensioner on the water pump? Belt is on the 'back' of the motor - the drivers side. If the thermostat was changed, they should have checked this, since it is all 'close by'.

But it sounds like classic head gasket problem. The Chevy mechanic doesn't know Northstars - they don't put water into the oil, a bad gasket usually puts coolant into the piston and it is burned out the tailpipe.

Have you checked your coolant level? If it goes down, the coolant is going somewhere.

Adding the coolant antileak tablets might pull you through this. If not, it's a lot of money to repair head gaskets on a Northstar.

09-15-04, 10:38 PM
P.S. Keep out of Mobile tonight.