My 2016 XC90 T8 seems to recently have an underperforming AC. I’ve never had issues with it keeping me comfortable set at 69 on a day that is 80+ outside, until now. It started when, periodically, the AC wouldn’t work on the driver’s side which would only blow tepid air and I thought I was headed for the dreaded evap repair. However, turning it off and on again seemed to resolve it. Other times, they’d all blow the same temp but just kind of tepid (it reached 85 outside and the AC, while cooler than that, simply couldn’t cool the cabin). If I put it at 62 or LO it seemed to do a bit better, but not how it usually behaved. I had it at the dealer, they noted that it had a proper charge and pressure, no observable leaks, and put out 60° air [normal, according to the report] during the AC test. They upgraded some software and recalibrated the blend doors. I haven’t yet experiened the driver side blowing warm again, but I still am not as comfortable as I used to be when driving around on an 82 degree day.
I picked up a gauge for the vent, and notice that it blows around 55° or so – set at MAX fan and LO temperature. It never dipped below. I then turned on the rear air and after a few minutes, the gauge dipped briedly to around 50 which actually started to feel more comfortable. After I turned the rear climate off again, the gauge resumed showing 55. I’m not sure why that would make any difference and I have yet to do another test but IMO, this performance seems inadequate. The exterior temp display seems correct and matches my 2007 XC90 and also other means of measuring outdoor temp. The interior cabin temp sensor is clean and free of debris.
The only recent change I can think of is that it had a new AC compressor installed (which is the 2nd one for this car) at the end of February. This is a high voltage component on the T8 and I fail to see why it’d be causing it directly. Given the temps, I hadn’t used the AC until last month when I noticed this. It could be entirely unrelated and, regardless, the system was evacuated, recharged, and tested for leaks at that time as well too.
So, two trips both confirming normal operation – perhaps in the passing PNW winter I’ve simply forgotten how the AC behaved over the years I’ve owned the car? Is there another cause? Could the condenser have taken some debris in these repeated services leading to reduced performance? If so, how do I explore that route or troubleshoot it?