C15 - water temp erratic - what could it be?

had erratic temp readings on Volvo engine after cooling system work. they had to "burp" the system, it had air in it. when they told me that ,I about died laughing. burp !!??

 

Have a 6TS that had erratic readings when watching it on ET. I think that we went through 4 sensors with that problem. It was always a different reason, but we were pulling our hair out.

 

nothing with the thermostats would cause the gauge to do what you describe. sounds like a wire grounding out, or a bad gauge. wires that bounce on the engine at different spots gradually over time wear thru the coating. could also be where the end of the sensor was plugged back in after inframe was not all the way in. check from the sensor that sends the signal to the dash gauge & follow the wires make sure no bare wires showing.

 

I thought C-15's used 185 deg thermostat ?

 

I wish I had a 195... The hotter the better I find.

 

I believe from 03 and up they went 195's to help keep emissions down and fuel mileage up.

 

Before you get to carried away, make sure that they reinstalled the ground strap from the engine to the frame.

 

I believe there are more than one? Also from the frame or motor to the cab?