Can you tell me why my car thermometer needle moves up and down?

Answer by  Amber40 (24961)

This could be caused by many thing. Check your temperature sending unit to make sure it is working correctly, check your coolant level, and make sure your cooling fan works.

Answer by  Teaberry (846)

The most common cause is a faulty thermostate. When this is bad, it will not give a correct reading and can sometime fluctuate the reading.

Answer by  randyrobinson2001 (86)

My guess would be you either most likely have a bad thermostat in the car that is not letting coolant through at the correct times, a bad fan clutch, a bad temperature sensor, or the most unlikely a bad temperature guage. I would replace your thermostat first, it relatively cheap and anyone can do it with a wrench

Answer by  sathish123 (2147483647)

I know that the thermostat has no bearing on engine temp once it opens. only mentioned it so people would know I'd already checked that it works I'm running 93 octane, one flat towards rich of nominal on the H6's Flex fan, valves adjusted to the tight side of Volvo's recomendations.

Answer by  Matt67 (112)

The thermometer is directly related to the coolant in the engine. As the engine heats up the coolant does too. Once at the correct temp the thermostat will open allowing the coolant to pass thru the manifold and radiator allowing it to cool as it passes thus cooling the engine!

Answer by  Gaur (7676)

I like the little braid detail between the cuff and mitten body too. A very, very cool technique! Once this first mitten is complete, I can move on to the second. His tail didn't heal from the last time and pretty much split back open where the stitches were.