Temperature Needle goes to the max. (94 Pontiac Sunbird LE )

Greetings,

First perform all the basics like changing the thermostat and radiator cap. Either of those could cause overheat problems with plenty of coolant in the system. If that doesn't work, check your airflow through the radiator (blocked by leaves or other crud or all the fins bent over) and the proper function of the radiator fan (could be a bad fan motor or thermostatic control switch). Lastly, you may need to get your water pump checked and the radiator flow tested to make sure it's not full of sediment and other crud on the inside. A good radiator shop should be able to diagnose your problem fairly quickly.

Cheers - Jonathan

First thing to do is determine if the engine is overheating or not. If not overheating the temperature sender could be bad.

There are at least two possibilities

The thermostat is not opening up when it should allowing the engine to get very hot before it finally does open and gets back to normal.

The sending unit is defective.

In my case, the needle went to the end and stayed there for anywhere from a minute to an hour. Your is probably a bit different.

Not if you live in Canada, Europe, or many other parts of the world. 125C =

What gauge are you looking at? 125 degrees is barely warm.

Take the radiator cap off and jack up the front end, then start it up. Let it get hot and see if you can burp the system..You just might have a air bubble in the cooling system.