Q: temp gauge in normal range, turn off car and electric fans are running. Open hood and coolant overflow tank is overflowing

asked by on September 10, 2016

Car seems to run fine.....was just surprised by the fans running on an 90 degree day in Virginia, and the overflow tank full with pressure behind it.

My car has 230000 miles.
My car has a manual transmission.

The cooling fans running on a 90 degree day is fairly normal for most cars. The coolant overflow full with pressure is also normal. As the heat of the coolant heats up and cools down this causes an expanding and contracting causes the pressure to build in the overflow tank. As long as the temperature remains normal this is normal.

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