I have a 970.2 2014 GTS

Although the fan is working, the AC on the two driver side front vents is not cold (not even cool) whereas the passenger side is cold. Running the heat will have a similar temperature bias with hotter air on the driver side. Not sure if the control unit is faulty or if the servo motor that controls the blending is faulty. It was working perfectly at lunch now it’s faulty. A restart and playing around with fan and temperature controls made no difference. Is this something the Durametric could help diagnose?

 

Durametric may help if there are faults in the climate system. From my experience it sounds like a blend door/actuator issue.

 

Does sound like the air mixer servo motor.
Small little stepper motor packaged into black plastic, that adjusts flow of hot/cold air into cabin. If motor dies (really doesnt die but doesnt go through its range anymore), the aur dies not get mixex right.
I have also seen similar behavior wher refrigerant is low, but more likely servo motor. I dont know on for it.
In my cayenne tt ultra mega pita to replace. Legendary threads about doing it. I have 3 to swap in that car. One day, one day.

 

I added 4 ounces of Freon and that fixed the problem. I’m getting cold air from driver and passenger side vents instead of only passenger side.
After hooking up the gage to the low side the pressure looked reasonable but decided to add a small amount as an experiment. I used one of those auto part store kits that have a gage integral with the low charging hose. The accuracy is unknown.
Longer term will track down the Porsche value for the low side and check with better gage.

 

From my experience, adding refrigerant can be as damaging as not having enough.

The way to add refrigerant to any car is to:
- have FSM that includes chart of temp vs pressure vs amt of refrigerant
- pull out all refrigerant out of system
- pull vacuum on system to about -27lbs and keep there for 30 minutes. vacuum should remain same otherwise leak is present
- fix any leak areas and replace the dryer cartridge
- turn on car and warm up
- turn on ac in car to full blast, and recirculation and let us idle for 10 minutes
- measure ambient temperature outside car
- use FSM charts to determine how many oz of refrigerant needed to fill car and what vent temp should be observed then
- use gauges to add prescribed amount of refrigerant
- monitor vent temp to ensure you get the temp FSM predicts

Adding refrigerant can cause more pressure on AC compressor and cause it to break later on.
I speak from experience. Added some into system because noticed one side was not cooling, then time later ac compressor went out.
In porsches, the stepper motors that control temp mixing are often reason a side does not work.

If you already put in gas, I would say warm up the car, put on full blast in recirculate mode, find the AC charts from FSM, connect gauges and see what the pressure is.
The FSM charts will show what pressure you should have at particular outside ambient temp. so at 90F, you should see hi/low pressure within tolerances FSM shows. If yours is higher, then you are overcharging your system.
I would do that to be on safe side. Take care.

 

970.2 4S with 4-zone climate control.

Noticed today that both my driver’s side air vents (closest to the rear view mirror + driver’s side of the PCM head unit) are blowing noticeably warmer air compared to the passenger vents. Rear vents are blowing cold too. Also hearing a new faint “hissing” sound when the system is running. Hissing goes away if the system is turned off (turning the fan all the way off). Thoughts and help?

 

Is this a quad zone panamera (front and rear, and left right controls), or 2 zone (front and rear)?

Two things come to mind.
1. Car running lower on refrigerant (when was ac last maintained and topped off,, checked for leaks)

2. Some of temperature mixing flaps are failing.

If you have piwus2, you can find out which of the Temp mixing servo motors are not working right, by testing each.

The hissing is the refrigerant going through the expansion valve, where it is converted from liquid to a vapor spray. Normal sound.

 

Yes, quad zone (all 4 seats have individual ability to set temperature).


Sound has been more pronounced last few weeks. I don’t remember it being this loud in the past.

I have a PIWIS 2. Is the process to check the servo motors pretty straightforward?

Thanks you!

 

Quad zone means more servo motors Temp mixing motors).
Many report putting in more refrigerant makes the warm vent blow cold, but I would caution against just putting in refrigerant without testing pressure. Easy way to destroy ac compressor.
I would say best way I'd with piwis, see if all servo motors work OK. If yes, next step is trip to ac shop (one that works on porsches), so they can evacuate, pull vacuum, make sure no leaks, then charge it all.

 

That is the same experience I had before the driver vents stopped working. Unusually loud hissing for weeks then the cooling stopped on the driver vents.

 

Yes @riden!! Hissing...that is a perfect way to describe the sound! Temperature difference is most pronounced on a hot day with the A/C on the lowest setting. Ice cold in the other 3 zones (passenger and 2 rear) and only mildly cool on the driver’s side.

Did adding some freon permanently solve your problem? Anything else? Thank you!!

 

I added Freon and haven’t had a problem since. Been working fine for 18 months now ( part of that was winter driving). If you do this yourself, be careful not to add too much, as @ciaka has warned.

 

If you do it yourself, get ac gauges (free loaners at autozone etc), find section in fsm, showing Temp vs r134a volume, and do it like that. And remember, ac system is fully sealed, if your ac lost pressure, it means some escaped, and it can only escape if there is a leak.

 

Connected PIWIS 2 to car and ran a diagnostic on servo motors (through air conditioning menu). All checked out okay. Car going to dealer in few weeks for suspected oil leak from valve or timing cover (again!). Will have them service A/C rather than doing DIY on this one. Have extended warranty hence dealer involvement.

FYI...used PIWIS for hours this morning with external power supply attached with no issues. Strongly recommend making one if doing any DIY work with PIWIS. Have posted on this in the past.

 

Good job.
if you have warranty, good call to let them handle.
You already paid for it.
I will be making the supply when parts arrive this week. Good info on that so thanks again.