Q: Heater and Coolant Leak

asked by on

I first noticed a small spot under my car in my driveway last spring, but it only happened a few times so I did not think much more of it. Now my heater is not functioning properly. It will kick out cold air at times with the heater on high and engine temp right in the middle of the gauge. Other times, mostly on highway driving or when I gun it, then the air will get hot again. The temp gauge in the car only creeped up twice. Once when sitting in a drive thru line and other time driving 55mph (but went down when I turned the heat/cold air on). I topped off the coolant (it was VERY low), and it appears in a few days the coolant level in the reservoir has already dropped some. Therefore, I assume there is a coolant leak somewhere. I would rather not jump to the conclusion to change the water pump due to the HIGH replacement cost, so are there some other things I can check first?

My car has 126000 miles.
My car has an automatic transmission.

In order to find a coolant leak, I would recommend enlisting the assistance of a qualified professional to perform a cooling system pressure test on your vehicle. This will pressurize the cooling system with the engine off. This will enable leaks to be found much easier without the wind from the cooling fan and the noise from a running engine. Some possible sources of leaks other than the water pump would be the radiator, coolant hoses, the engine itself, or the heater core. I would recommend having all of these parts visually inspected as well to verify where the leak is coming from. YourMechanic offers a repair and diagnosis service preformed by a mobile, professional mechanic that will commute to your location to resolve your coolant leak.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1,000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. Heater and Coolant Leak

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: Brake pedal has too much play.

Brake issues are always a big concern for any driver. I am going to assume from the description provided that both the front and rear brakes were replaced on your vehicle. If, despite these new parts, you are still experiencing...

Q: Drives, but doesnt shift out of first gear

Automatic transmissions are tricky. It may be the same problem again. If it is you need to look further into why the solenoid is continuing to fail. There is going to be a power supply or similar issue that is...

Q: Car won't start - 2011 Lexus ES350

Hi and thank you for contacting YourMechanic. Even though your accessories are still functioning, the rapid clicking noise you are hearing is the battery not having enough power to turn your engine over and start. If your battery does not...

Related articles

P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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.