As soon as i start the car the needle goes to H

[Kabhisheikh]

i have 1998 Impala and as soon as i switch on my car the thermostat needle goes to H could this be a needle problem or is it overheating as soon as i start the car

how can i check

[chevindiguy]

If car AC fan isnt working even AC s off, this can happen as AC fan has two functions: Must switch on while AC is on and Second function is it shud switch on while car is overheating. In summer now car is more prone to overheating at idle.

If AC fan and engine fan is fine, then do the manual check to see if water temperature sending sensor is fine or not.

When car overheat step out and open hood and press both the radiator hoses (thick black ones). If its hot as hell and hard as metal that means car is actually overheating and have enough pressure build up inside to make those hoses so hard.

If you can press those hoses by hand atleast 25% or more of their size then for sure its water temperature sensor is faulty and sleepy.

If one hose is hot and hard and other one is soft and warm then your thermostat isnt opening in time and you need to change that first..

[Kabhisheikh]

thank you for the information.