Q: Temperature gauge goes up and down

asked by on October 01, 2017

I was drag racing for a while, then when I parked my car, I noticed that boiling water was falling from the car, quickly had a look at the temperature gauge and I can see that it reached 3 quarters.

Then I took my car to the fuel station and I requested somebody to put water to the water container ( linked to the radiator) , then steam and pressure started to release, however when he opened it, water level was not low, it was above half the container.

I had a look under the hood and I can see that the fans are cooling very well.

Then I returned home and on the way, the heat gauge goes up and down. regardless of the situation. I tried the following scenarios:

  • Flooring the gas pedal
  • Stopping the car
  • putting the AC on
  • going fast
  • going slow They don't really affect the fuel gauge and it just keeps going up and down ( doesn't reach MAX though.. it reaches to 3 quarters only)

However, when I set the cruise control and go in a fixed speed, temp gauge stays low

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You’re probably low on coolant. Filling the reservoir doesn’t really do the trick for filling the cooling system. There is probably air trapped in the cooling system that needs to be bled out. You may be able to do it yourself without extreme measures. Starting with a cold engine, start the car and set the climate control to max heat. Take off the radiator cap and fill the radiator, not just the reservoir. let the car idle with the radiator cap off , adding coolant as the level drops until the engine is fully warmed up and the heater is blowing hot. This might take as much as half an hour. Then put on the cap and see how it does. If this doesn’t work out, contact YourMechanic. They will send a technician to your home or office to check out your overheating problem and let you know what it will take to solve it.

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