2018 CX9 GT AWD, AC cool but not cold

Hey All,

My 2018 Mazda CX9 GT AWD has about 42K miles on it.

I'm noticing that the AC performance is not what it once was. It's cool but not ice cold.

Anyone else running into this?
 
I have 2021 CX 9 Grand Touring, the AC is ok but not great. From day 1 I noticed that the AC is weaker than any other car I have owned. Especially in hot days I cant have it pull fresh air from outside, it has to be on Air circulation mode all the time in order to be able to cool properly. Also the AC is weak when idling, once I move forward its ok
 
You should check your coolant level ASAP. And I hope the problem is not what I'm thinking it might be.

I do not think that I have any leaks or punctures in my condenser. Last summer my other car had a rock hit the condenser which created a pinhole that allowed the R134a to leak out. $3500 in repairs. As luck would have it, comprehensive covered it with a $100 deductible.

As for the CX9, I stopped by two of my local Indies today. They both told me the same thing -- 'R134a is good for 3-4 years before it begins to degrade'. They both suggested a complete purge and refill (for between $135-150). I'm going to head to the Indie with the newest AC equipment and see how that goes.

Thoughts?
 
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2016 CX-9 GT
I’ve noticed that in this Texas heat, my wife’s 4Runner can cool the car at idle, but my CX-9 doesn’t cool very well until I start moving. Not super helpful to OP, but provides another data point. I’d be interested to see what you think after the shop “fixes” it!
 
I’ve noticed that in this Texas heat, my wife’s 4Runner can cool the car at idle, but my CX-9 doesn’t cool very well until I start moving. Not super helpful to OP, but provides another data point. I’d be interested to see what you think after the shop “fixes” it!
My CX9's AC (in the northeast) was perfectly fine summers 2018-2021; for 2022, it's not performing nearly as well.

I'll report back after I throw $135 at the problem. :)
 
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Northeast
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2020 CX-5 Tour
I wasn't referring to a condenser leak. The big, systemic issue with a group of newer Mazda turbo engines (including the CX-9) is a coolant leak coming from a cracked cylinder head. That's why I suggested checking the coolant level, because if the engine is running hotter due to low coolant, that can have an effect on AC performance as well.

But regardless of that, saying that R134a degrades enough in 3-4 years to affect AC performance is 'aggressive' IMO, with 7 years+ being the more typically stated R134a longevity.
 

speed3chris1

2021 Signature CX-9
I had a 2016 and now a 2021. The air conditioning at best is cool but not cold. Things have not changed over the years. When 2016 hit the market that was the biggest issue with new owners. I have had lots of Mazdas and the air conditioning has been very cold. It's too bad they haven't addressed this issue after 7 years.
 
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2016 CX-9 GT
My CX9's AC (in the northeast) was perfectly fine summers 2018-2021; for 2022, it's not performing nearly as well.

I'll report back after I throw $135 at the problem. :)
Yeah, we moved from the northeast to TX. AC was more than adequate in NE. TX is different. Threw a remote start in to try and help a bit with the lacking AC, but I’ve grown to just accept my vehicle will be hot until I get on the freeway.

If there’s a noticeable difference that you report back, I’ll have someone take a look at it. Our two vehicles are only a year apart so I don’t think it should be a refrigerant based problem though
 
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Mazda CX-9 Grand Touring 2016
They both told me the same thing -- 'R134a is good for 3-4 years before it begins to degrade'. They both suggested a complete purge and refill (for between $135-150).
Nonsense and a rip off. Refrigerant does not degrade. It will work fine for ever unless a contaminant enters the system or the refrigerant leaks out. There is no "purge." What they'll probably do is maybe add some unneeded R134a to your system or maybe pull out your refrigerant charge into their recovery machine and be sure the correct amount of your same refrigerant is put back in. In either case, don't. If there is contamination in the system it may be purged with an inert gas like CO2 then drawn down to a deep vacuum before recharging. This is only in the case of contamination, not due to a weak output.

I have a reefer tech certificate. I've run and repaired systems using R-11, R-12, R-22, R-502, and R-134a. Centrifugal, piston, screw, and scroll compressors. Never, ever had degraded refrigerant. Any loss of capacity was due to something I had to repair. Once I found and fixed the problem, and put the same good old used refrigerant back into the unit, it ran like new.
 
Nonsense and a rip off. Refrigerant does not degrade. It will work fine for ever unless a contaminant enters the system or the refrigerant leaks out. There is no "purge." What they'll probably do is maybe add some unneeded R134a to your system or maybe pull out your refrigerant charge into their recovery machine and be sure the correct amount of your same refrigerant is put back in. In either case, don't. If there is contamination in the system it may be purged with an inert gas like CO2 then drawn down to a deep vacuum before recharging. This is only in the case of contamination, not due to a weak output.

I have a reefer tech certificate. I've run and repaired systems using R-11, R-12, R-22, R-502, and R-134a. Centrifugal, piston, screw, and scroll compressors. Never, ever had degraded refrigerant. Any loss of capacity was due to something I had to repair. Once I found and fixed the problem, and put the same good old used refrigerant back into the unit, it ran like new.
Agree, CX-9 AC is weak( we have to accept this fact). Mazda should've upgraded the AC by adding more BTUs(bigger compressor, condenser, etc) after the issue first reported in 2016.
 
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2018 CX-9 GT
Unlikely to be related to engine overheating or coolant leak. The AC runs on a totally separate circuit than the engine coolant. Even if it was a factor, you can easily check coolant temp with the in-dash temperature gage.it should be staying in the middle.
 
I have 2021 CX 9 Grand Touring, the AC is ok but not great. From day 1 I noticed that the AC is weaker than any other car I have owned. Especially in hot days I cant have it pull fresh air from outside, it has to be on Air circulation mode all the time in order to be able to cool properly. Also the AC is weak when idling, once I move forward its ok
I have EXACTLY the same condition on my 2020 GT. WTF it can't cool AT All on fresh air mode and only just OK on recirculating mode. Something has to be wrong
 
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18 Mazda CX5 AW
All my previous fords, toyotas, vw and chevys had very cold AC. When got this car, took to dealer to have warranty items fixed. Mentioned that it isnt cold and that fan doesnt blow fast. There solution was to say AC was properly charged and recommend changing cabin filter. Mazda AC is one of the few disappointments with the vehicle.
 
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Mazda CX-9 Grand Touring 2016
I'd check the AC performance with two thermometers. One at the air inlet (I don't know where that is when running recirc...somewhere under the dash, I guess) and one at an air outlet. If there is about 20°F difference or more (say, 100 in and 80 out), the machinery is doing all it should. If that doesn't cool the cabin enough, then the air conditioning machinery is just too small for the job. If the difference is less than about 20° then there is a problem.

One problem to consider is that a flapper on a hot air heating duct isn't closing tightly. The AC might be doing fine, but somewhere in the duct hot air is mixing with the cold. Try moving from full warm to full cool and back several times. Give it time to work each way. If that frees something up, great. If not then it needs a shop repair.

Try removing the cabin air filter. It isn't a necessity. This isn't a fix, just a check.

At idle the engine and the connected refrigeration compressor are running more slowly. Output will be less.
 
I'd check the AC performance with two thermometers. One at the air inlet (I don't know where that is when running recirc...somewhere under the dash, I guess) and one at an air outlet. If there is about 20°F difference or more (say, 100 in and 80 out), the machinery is doing all it should. If that doesn't cool the cabin enough, then the air conditioning machinery is just too small for the job. If the difference is less than about 20° then there is a problem.

One problem to consider is that a flapper on a hot air heating duct isn't closing tightly. The AC might be doing fine, but somewhere in the duct hot air is mixing with the cold. Try moving from full warm to full cool and back several times. Give it time to work each way. If that frees something up, great. If not then it needs a shop repair.

Try removing the cabin air filter. It isn't a necessity. This isn't a fix, just a check.

At idle the engine and the connected refrigeration compressor are running more slowly. Output will be less.
Yes but since the AC is borderline it reveal its weakness when idling. Other vehicles have extremely powerful AC that even if you idle and it gets slower doesn’t matter that much!
 
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18 Mazda CX5 AW
Yes but wince the AC is already borderline it reveal its weakness when idling. Other vehicles have extremely powerful AC that even if you idle and it gets slower doesn’t matter that much!
Yee. Agree.

Not a defect. Warranty useless. (Unless the dealership lied- but based on the amount of people that are having problems...)

Not a maintenance issue.(refrigerant and air filter ok)

This appears to be a platform production problem(at least in the CX5 and CX9) with the only fix to be get another brand car or modify your AC with bigger compressor(and higher output, quieter fans), if thats even possible. Or just live with it as-is. Luckily where I live there is only four(4) hot months.
 
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Yee. Agree.

Not a defect. Warranty useless. (Unless the dealership lied- but based on the amount of people that are having problems...)

Not a maintenance issue.(refrigerant and air filter ok)

This appears to be a platform production problem(at least in the CX5 and CX9) with the only fix to be get another brand car or modify your AC with bigger compressor(and higher output, quieter fans), if thats even possible. Or just live with it as-is. Luckily where I live there is only four(4) hot months.
Here in the northeast its not too hot as well, only two months only July and Aug.