[KingRevo]

My water temptrature gauge is a bit tempramental.

Jumps around all over the place when I'm driving. Once it got to the top but I stopped and the engine was pretty cool so I dont think it is over heating.

Sometimes it will start (from cold) in the red and then move down to 80 after a few miles.

Can anyone tell me what part I need to order, or where abouts the sensor is so I can check it?

There seems to be a sensor on top of the rad but this appears to just be the coolant LEVEL sensor, or does it do temprature as well?

 

[acousticplayerjb]

what year and model? I have a 2000 c230K and there is only 1 sensor for coolant. Some models have 2 sensors.

 

[KingRevo]

Sorry, it's a 1994 C220 Petrol

 

[acousticplayerjb]

I think it would be just that sensor then. It'd be the part that you see in the picture on this page: http://www.benzworld.org/forums/w202-c-class/1460683-coolant-temp-sensor-location-required.html

First though, look around at your wiring and make sure that there aren't any cracked or brittle wires. If there are, that may be part of your issue.

If you have a multimeter, you can test the resistance of the sensor by unplugging the cable and just attaching it to the two leads in the sensor. The resistance value should change depending on whether the engine is cold or at operating temperature. If there is no change, or there is no resistance at all, then that is the sensor you'll want to replace.

 

[KingRevo]

Thanks, will have a look