I have a 94 gmc sierra that is over heating.?

[Heath James]

It has new water pump, new radiator, new radiator cap, 4 new thermostats, and the fan works. When I'm driving or letting it idle the temp starts to go up, but if I stomp the gas sometimes the temp goes back down. I would say it is the thermostat but what are the odds of me getting 4 bad thermostats in a row. Right now I am running without a thermostat and I don't have a problem with the temp, but ever time I put one in it overheats.

 

[tootall]

Make sure belt ain't slipping or you don't have underdrive pulleys do you?Also coolant level isn't dropping is it?

 

[jesus gonzalez]

It might be the inside heater core
the one used for the heater.its under the glove box.check your carpet to see ir is wet or the front window for consensation from the heater core leeking.if not you have a air pocket inside your motor.

 

[Tim B]

the thermostats have different temp ratings, get one with a lower temp rating and see if that helps.

 

[honker]

All this time you have not lost water either. Seems you might have a bad radiator. I had the same head hair plugging frustration until some friend says its my radiator. It might be new but it can be bad too. Tool it to a radiator shop found many of the tubes were clogged.

 

[honker]

All this time you have not lost water either. Seems you might have a bad radiator. I had the same head hair plugging frustration until some friend says its my radiator. It might be new but it can be bad too. Tool it to a radiator shop found many of the tubes were clogged.

 

[Joseph]

sounds to me like the sending unit is on the way out. how does the radiator look. if you see what looks like build up in it then you need to flush the rad. with a good flush that will eat the scale with out harming the rad.

 

[knuckleheaf27]

try burping your cooling system..... air in the system could cause problems like this....