Skip the auto shop - Our mechanics make house calls

Q: I have a 2004 Kia SuV. Air conditioning works ok except when I go up a hill. Then it cuts out and may or may not come back on. I the

asked by on

I have a 2004 Kia SuV. Air conditioner works ok except when I go up a hill. Then it cuts out and may or may not come back on. I the car levels to a flat area, the air will still not work. any suggestions?

My car has 147000 miles.
My car has an automatic transmission.

A: I suspect you have a cooling system issue o...

I suspect you have a cooling system issue or low refrigerant. When you are climbing a hill, your car is experiencing increased load that produces as much a ten times more heat than if it were cruising on a flat. Your condenser is mounted at the front of your radiator and adds heat to the radiator. When you are climbing a hill, if your cooling system has any problems, it will not be able to dissipate the extra heat. Two things can occur as a result of this. The car can choose to turn your A/C system off or the condenser will not be able to keep the high side of the A/C system cool enough. When the high side of the A/C system gets to hot, the pressure rises and the pressure switch will turn the compressor off. Both of these issue has to do with insufficient cooling.

In the case of low refrigerant, as the system continues to run for an extended period of time, the low side pressure will become to low and the compressor will cycle quickly. At this point you will get intermittent moments of cool air. But never as cool as it should be. What's happening is once a low system pumps most of the refrigerant to the high side, it leaves the low side at a deficit. It will stay this way until the you turn the A/C off for a time and allow the pressures to equalize.

Either way, you should have both your A/C system serviced and your cooling system inspected by a certified technician, like one from YourMechanic. One of our mobile experts will be able to come to your home to do so.

Good luck!

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 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!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Noise coming from area of belts. I think it may be the ac compressor or compressor clutch

The car is safe to drive, but you probably won't have air conditioning. The main thing you want to consider is the A/C belt also driving the alternator. If the compressor clutch bearing locks up, it will break the belt...

Q: Ac not cooling properly.

Hello. Thanks for writing in about your 2005 Toyota 4Runner. You could try purchasing another thermometer to check the level, but the system's instruments don't typically give false readings. The conditions outside can affect the operation of the system as...

Q: have code p0017 dealer is telling me i need a new engine is this because they dont know what to do next to my car .?

As you may have already learned, the code p0017 indicates an issue with the crankshaft position sensor. This would mean that that transmission doesn't understand the speed and can't send the same information to the transmission. I don't think your...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.