AC system issues

[QuadFin]

When I run my AC it makes a hissing* sound and blows warm air. Initially the noise would stop when I turn the AC off or switch to Track mode. But, now the issue is there even when the AC and fan are off. (*Best I can describe it, is it sounds similar to filling a scuba tank or an air compressor tank coming up to pressure.) The noise isn’t immediate; it takes a few seconds to build after the car is started and running. Also, the noise doesn’t change when pressing the go pedal.

I haven’t picked up high and low pressure gauges to check the pressure on the system. I’ve tried pulling all the fuses for the AC system but that didn’t resolve the issue. I scanned for DTCs and nothing came up. I also checked the low side pipes when the AC was running and they didn’t get cold; which leads me to believe here is a leak.

My knowledge is limited, at best, with HVAC systems. Does the AC system still activate when the AC isn’t on in the cabin or the car isn’t in Track mode? Could a leak cause this noise if the system isn’t coming up to pressure? Any suggestions on what to check or try next? The “comprehensive” service manuals are, in my opinion, anything but. So, I made an appointment with the dealer.

Separately, any recommendations for an ODB2 scanner that supports actuator/module testing for Hellcats? The ODB2 scanner I have doesn’t support actuator/module testing for current gen SRT Hellcats. Although, it did give me an alert that the throttle body has a 40% chance of failing in the next 10k miles. 😕 At least it has a 60% chance of living longer than 10k miles…. 10,001 miles?

Appreciate any suggestions on where to look into next. Thanks all!

BTW - 2019 Hellcat Redeye with 9,100 miles.

Edit: Adding video of noise.

 

[Magnified]

The Track Mode part mystifies me

 

[2fast4u]

track mode kicks the A/C out on throttle.

 

[QuadFin]

The Track Mode part mystifies me

Switching to Track mode activates the chiller and diverts the cabin AC to the chiller. Because of that I thought it was a blend door/actuator at first.

 

[Magnified]

I knew that but forgot... damn you time!

 

[Linda's Hell Cat]

I'll just throw in.... Check your thermostat.
Linda

 

[Mean Cat]

That noise your hearing just may be the pressure changes from when it goes from cabin air to chiller only or vise versa, until it equalizes out.

 

[Paladin06]

When I had that issue, I had mistakenly left the chiller on. Check your settings in Uconnect screen.

 

[QuadFin]

I'll just throw in.... Check your thermostat.
Linda

Thanks Linda. Checked, and all appears good with the thermostat.

 

[QuadFin]

That noise your hearing just may be the pressure changes from when it goes from cabin air to chiller only or vise versa, until it equalizes out.

Thanks Mean Cat. I had that thought as well until it started making the noise with the AC off with everything set to Street mode. Then I thought there might be a vacuum leak, but car is running fine except the noise and no AC.

 

[QuadFin]

When I had that issue, I had mistakenly left the chiller on. Check your settings in Uconnect screen.

Double checked that the chiller was off and the noise is still there.

 

[Hickster]

Yo Quad,
Have any freezing up problems?? Supposed tp be a closed system with any leaks would freeze up the cold side. May need a shot of blow wih a leak check. Did you add the chiller?? If did then was the difference made up on gas>>>

 

[Linda's Hell Cat]

Yo Quad,
Have any freezing up problems?? Supposed tp be a closed system with any leaks would freeze up the cold side. May need a shot of blow wih a leak check. Did you add the chiller?? If did then was the difference made up on gas>>>

Come on @Hickster This is your expertise and best to answer
Give him the other writing !

You can do it!

 

[Hickster]

Not yetster. Got enough shine for a girly glass then back to red whine is so fine. Been dry for 3 days.

 

[Mean Cat]

Thanks Mean Cat. I had that thought as well until it started making the noise with the AC off with everything set to Street mode. Then I thought there might be a vacuum leak, but car is running fine except the noise and no AC.

OK, I hate to say it but this may be one of those issues that the dealer (if not figured out) needs to look at ?

 

[Hickster]

Not runing GOOD Nuff.

 

[QuadFin]

Yo Quad,
Have any freezing up problems?? Supposed tp be a closed system with any leaks would freeze up the cold side. May need a shot of blow wih a leak check. Did you add the chiller?? If did then was the difference made up on gas>>>

Thanks Hickster. Chiller is stock on RE/Demons. Didn’t notice any freezing. Apparently blow is easier to get than freon in California, so it’s either off to a shop or the dealer; which I was hoping to avoid.

 

[DodgeCares]

When I run my AC it makes a hissing* sound and blows warm air. Initially the noise would stop when I turn the AC off or switch to Track mode. But, now the issue is there even when the AC and fan are off. (*Best I can describe it, is it sounds similar to filling a scuba tank or an air compressor tank coming up to pressure.) The noise isn’t immediate; it takes a few seconds to build after the car is started and running. Also, the noise doesn’t change when pressing the go pedal.

I haven’t picked up high and low pressure gauges to check the pressure on the system. I’ve tried pulling all the fuses for the AC system but that didn’t resolve the issue. I scanned for DTCs and nothing came up. I also checked the low side pipes when the AC was running and they didn’t get cold; which leads me to believe here is a leak.

My knowledge is limited, at best, with HVAC systems. Does the AC system still activate when the AC isn’t on in the cabin or the car isn’t in Track mode? Could a leak cause this noise if the system isn’t coming up to pressure? Any suggestions on what to check or try next? The “comprehensive” service manuals are, in my opinion, anything but. So, I made an appointment with the dealer.

Separately, any recommendations for an ODB2 scanner that supports actuator/module testing for Hellcats? The ODB2 scanner I have doesn’t support actuator/module testing for current gen SRT Hellcats. Although, it did give me an alert that the throttle body has a 40% chance of failing in the next 10k miles. 😕 At least it has a 60% chance of living longer than 10k miles…. 10,001 miles?

Appreciate any suggestions on where to look into next. Thanks all!

BTW - 2019 Hellcat Redeye with 9,100 miles.

Edit: Adding video of noise.

Hi QuadFin,
Glad to hear you are working with your dealer for this concern. If we can be of any additional assistance as you are working with your dealer, feel free to send us a private message. We'd be more than happy to help.

Rob
Dodge Cares

 

[Tape]

If the low pressure line isn't cold and sweating then it's not pumping any gas = LEAK