Skip the auto shop - Our mechanics make house calls

Q: Squealing noise when you start the car

asked by on

If the air conditioning is on it makes a loud squealing noise. We've changed belts wigh no kmprovement

My car has 2282452 miles.
My car has an automatic transmission.

A: Hi there. Depending on the engine and type ...

Hi there. Depending on the engine and type of car you have, it may change the diagnostics. I suggest checking the a/c belt tensioner for proper tension on the a/c belt. If the tension on the belt is okay and the tensioner is okay, then the a/c compressor is causing the belt to squeal due to a locked up compressor. If the noise goes away when a/c is off and comes back with a/c on, then the compressor will need to be checked to see if it is locking up. This is due to having a bad compressor or a blockage in the system causing the high pressure side to be blocked. The condenser or expansion valve and drier may be blocked. I recommend having a technician, like one from YourMechanic, inspect the air conditioning system and replace any failing parts.

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: Water leak on passenger's side

Hello. It sounds like you may have a clogged AC drain hose. Overtime, the drain hose can become clogged with debris and restrict the water drain passages. There should be a little hose coming out of the firewall into the...

Q: How do you use the headlight switch?

Your car is equipped with headlights that should be used when driving at night, as well as in many other situations when ambient light is low or visibility is obscured (when it’s raining, in fog, when it’s misting, etc.). Of...

Q: Steering wheel vibrates while braking.

The people you talked to were all correct in a way. With an unbalanced tire, you will not feel the vibration at slow speeds. You will only feel it once the vehicle gets faster. It sometimes goes away with increased...

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...
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 P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...