Q: Overheats when heater is on, heater blows cold air.

asked by on

I just had the heater core bypass hose assembly replaced two weeks ago due to a very bad leak. Car was running fine after the repair, no temp problems, until I turned the heater on today. Within five minutes the temp gauge was almost all the way up while the heater was still blowing cold. The heater used to work great before the repair, save for a slight coolant smell when turned on. Now it blows cold while the motor overheats! That's the opposite of what I need!

My car has 233000 miles.
My car has an automatic transmission.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Overheats when heater is on, heater blows cold air.

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Can you reset or bypass traction control?

If you just put on new tires only in the rear and not in the front then the tires need to be checked to see if there is a difference in the tire height. This will cause the wheel sensors...

Q: Heating blows cold - 2006 Porsche Cayenne

Hello. Based on what you have described, I am almost 100% certain you need to replace your blower motor control module / resistor. Not getting AC is much more common than not getting heat because heat comes from the hot...

Q: Leak under car

Hello. It sounds like there may still be a coolant leak which could explain why the engine needs coolant light comes on a few days after adding coolant. A certified mechanic, such as one from YourMechanic, can do a coolant...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.