Q: My heater only blows out hot air when going down the road and rpms reach about 2 if or when i slow down or stop it blows cold

asked by on December 18, 2017

my heater only blows hot air when driving down the road, rpms close to 2, if i slow down or stop it blows cold air normally when rpms below 2

My car has 200000 miles.
My car has an automatic transmission.

This can sometimes happen when the coolant level is low or leaking. The coolant gets hotter as the RPMs rise. This can cause hot coolant to reach the heater core during high RPMs but not low RPMs. I recommend having your cooling system inspected by a qualified professional to determine if there are any leaks. If any leaks exist in your cooling system I would recommend having the leaks repaired and the system topped off with new coolant in order to resolve this issue. Consider YourMechanic as this can be done at your home or office.

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