A/C intermittently warm (2014 Jetta)

[gregk24]

I have noticed this behavior over the last month. When driving along with the A/C on it will randomly start to blow warm (or rather just not ice cold) for about 10 seconds, then it will start blowing cold air again. This seems to happen primarily when my foot is off the gas (coasting). Also of note, the air smells stale when this happens. Any idea what would be causing this. It is on my wifes 2014 Jetta SE 1.8 TSI. Currently it has around 55K miles.

 

[mk378]

Does it have a compressor clutch or variable displacement? If it's a clutch, the clutch isn't engaging all the time due to either excessive air gap (wear of the clutch plate) or bad relay. If variable displacement it is likely getting stuck at zero and the only cure there is replacing the compressor.

 

[gregk24]

Originally Posted by mk378
Does it have a compressor clutch or variable displacement? If it's a clutch, the clutch isn't engaging all the time due to either excessive air gap (wear of the clutch plate) or bad relay. If variable displacement it is likely getting stuck at zero and the only cure there is replacing the compressor.


It has a variable displacement compressor.

 

[Chris142]

Originally Posted by gregk24
Originally Posted by mk378
Does it have a compressor clutch or variable displacement? If it's a clutch, the clutch isn't engaging all the time due to either excessive air gap (wear of the clutch plate) or bad relay. If variable displacement it is likely getting stuck at zero and the only cure there is replacing the compressor.


It has a variable displacement compressor.

You can replace the compressor control valve. Common failure.

 

[LazyDog]

You can replace the compressor control valve. Common failure.

My vote is on this first!!!

 

[A_Spruce]

Similar issue with my '03 Suburban, everything fine, then it blows cold, dank, air for a few minutes then back to cooling. In my case it was low freon, mechanic said it was 24oz low

 

[FordBroncoVWJeta]

My dads 2012 Jetta does it too. I thought it was normal for gas mileage.

 

[gregk24]

Originally Posted by FordBroncoVWJeta
My dads 2012 Jetta does it too. I thought it was normal for gas mileage.


How long has it been exhibiting this behavior? Also how many miles and what engine does he have, 2.5?

 

[FordBroncoVWJeta]

Originally Posted by gregk24
Originally Posted by FordBroncoVWJeta
My dads 2012 Jetta does it too. I thought it was normal for gas mileage.


How long has it been exhibiting this behavior? Also how many miles and what engine does he have, 2.5?

It has the 2.slow. 140K miles. It's been doing it as far as I can remember.
Thinking about it I think my 17 does it too. It hasn't been hot enough to notice it this year, but I vaguely remember doing it last summer. Its only noticeable on very hot days.
They both do it when its in neutral. Coasting to a stop.
I might be getting the 17 mixed up with the 12 but im still pretty sure they both do it.

 

[vivaUkraine]

My car is an early 90s MB, but the exact same issue was resolved by replacing monovalve/heater control valve. If your car has it, that's the culprit