Back to all

Your Vehicle's Hissy Fit (AC System)

November 19, 2023

When you hear hissing sounds coming from your vehicle, you might start thinking the worst.   One type of hissing coming from around your air conditioner may be a normal sound, or it could be a sign of serious trouble.

First - the normal sound.  When you turn off your vehicle, the refrigerant goes from its high-pressure side to the low-pressure side. Some of those noises are normal.  But when it hisses all the time, that's another story.

One cause could be that the refrigerant is leaking.  Air conditioners are fairly complex systems that involve various pumps, hoses, valves and motors.  When your air conditioner is cooling, the refrigerant changes from a gas to a liquid and back.  That refrigerant is under pressure, and there are many places it can leak from. 

A hissing sound can also be a failed valve in your air conditioner's compressor.  It is what controls the refrigerant's pressurization.  It's important to have this fixed fairly quickly after it develops a problem because when it isn't, that can lead to more extensive—and expensive—repairs.

If you hear screeching coming from your air conditioner at the same time you hear hissing, your compressor may be on its last legs. It could also be a defective clutch. 

Any time you hear a noise you haven't routinely heard before, bring your vehicle to us so a technician can check the various components and properly repair the problems.  Air conditioning systems are complex and are best handled by a professional with the right tools and equipment.  When your AC has a hissy fit, let us cool it off and you at the same time.  

Gary Knurek GoodYear
1973 Livernois
Troy, Michigan 48083
248-362-0350

Need Service?

Request a Quote

More articles from Gary Knurek, Authorized GoodYear Dealer

You Are the Fluid Detective! (Leaking Fluids)

February 15, 2026

When you see some liquid sitting underneath your vehicle, your mind starts churning. Is that normal? Is that something serious, or did I just spill my drink? Heres a quick list of what those fluids look, smell and feel like, as well as what they might be. No, we dont recommend you taste them to ... More

Gearing Up (Differential Fluid Service)

February 8, 2026

You may have never thought about it, but when you turn a corner, the wheels on one side of your vehicle turn at a different speed than the other side. What is this magic? The answer is something called the differential. A differential is a gear box placed between the drive wheels and needs lub... More

No Charge (Why Won?t My Battery Hold a Charge?)

February 1, 2026

When your vehicles battery is dead, it leaves you with that horrible, helpless feeling. A dead battery means it wont hold a charge, and there are several reasons it wont. One is age. Batteries have chemical and electrical systems in them that create power, and as time goes by, they wont work we... More