superboyg

Since couple weeks ago, I found the water temperature is way too low, on highway, it never can raise up to the warmed up temperature(176F), it constantly moving around 131 to 149F, the longer you driving at highway, the temperature going lower, the outside temperature is around 68F. It could only raise to the normal temperature at the indoor carpark or traffic.

I did replaced the thermostat but it doesnt help, does anyone has the same experience and advice? Thanks

6speed mates advised someone did went thru this related to the value of the tip, hope so I could have more information.

Carlo_Carrera

Check out this thread. Are you sure the valve you replaced it working properly?

https://rennlist.com/forums/996-turb...emp-p0116.html

slant911

Could your gauge or instrument cluster be shot?

Macster

You have to be sure the temperature variation you are seeing is real and not a sensor acting up.

Ideally you need to view the engine coolant temperature in real time using an OBD2 code reader/data viewer and confirm that the temperature is right using an infra-red thermometer to verify the temperatures of the various areas of the block and water pump are about the same temperature.

If the temp gage and OBD2 data and the infra-red thermomstat numbers are in disagreement this suggests a temperature sensor problem.

If the numbers from the above sources are in agreement this suggests the cooling is real.

The thread posted by Carlos_Carrera then has some info that might be of help you. I'm not sure what valve is being referred to as the "heater valve" but in the case of the OP of the above referenced thread it was the cause of his car running cool.