I've got a 2013 Sonic LT. Back in December, I'd had the car in the dealership due to someone putting something in my gas tank. I'd had the whole engine replaced, as well as everything having to deal with the fuel system. I had roughly 85k miles on the car at the time. Now, I've had the car back for about a month, and I'm now sitting at 88k. Last week, the AC went warm, and started to hiss. I assumed it might be the refrigerant, so I took it in yesterday, and had it recharged. Now, the AC is cold, yet I still get the his at times. It's not constant, nor is anything about it consistent(length, loud/soft, when it happens). I know very, very little about cars, and I usually just follow the manual for maintenence. I get my oil changed when the indicator is at 5%. I like to think that, though I drive the hell out of it (I travel for work), that I take quite good care of my car. But I'm just wondering if this is something I should take it in for, or if it's something that will go away once the refrigerant settles?
Hissing from AC
- Thread starter Prayos
- Start date
Natesriv
Lead Foot
there shouldn't be any settling, the coolant is installed with oil, which lubricates the system. It's only supposed to be added as the system is running to get it moving...
If it gets warm again, then you have a leak. They can add a dye to the next recharge (if they didn't already on this last one) and find it with UV light....
If it gets warm again, then you have a leak. They can add a dye to the next recharge (if they didn't already on this last one) and find it with UV light....
Chevrolet Customer Care
New member
Hey Prayos,
If you need any additional assistance, please feel free to send me a private message along with your VIN, current mileage, contact information and preferred dealership. Looking forward to your updates.
Patsy G
Chevrolet Customer Care
ChrisJ
Active member
I think the Sonic may have a TXV (Thermostatic eXpansion Valve)in which case inconsistent hissing could indicate the valve is being starved of liquid which means running low on refrigerant.
Why did the system lose it's refrigerant? Where was the leak and was it repaired? A modern R134A system with barrier hoses shouldn't need a charge more than once every 10-15 years and even then it should only need to be slightly topped off.
Just an FYI, starving a TXV of liquid (running the system low on refrigerant) can result in flash gas which will damage the TXV. The chances of a tech working at a dealer knowing this are slim to none but the danger is real and if it gets damaged it will be your A\C system working poorly not theirs.
Why did the system lose it's refrigerant? Where was the leak and was it repaired? A modern R134A system with barrier hoses shouldn't need a charge more than once every 10-15 years and even then it should only need to be slightly topped off.
Just an FYI, starving a TXV of liquid (running the system low on refrigerant) can result in flash gas which will damage the TXV. The chances of a tech working at a dealer knowing this are slim to none but the danger is real and if it gets damaged it will be your A\C system working poorly not theirs.
boricuadude12
New member
I could swear that a hissing ac is very normal.. My ac hisses when the air gets colder. Im pretty sure thats intentional. I don't know the mechanics of it but I know it is part of how the ac works. Like when you press the gas and the engine revs, my ac hisses and then it gets colder.