Dwad

Hi guys,
​​​​​​My ac as not working & through the test I believe that the evaporator sensor is bad, now I got a new sensor & want to install it, unfortunately I don't know the location of it & how many hours it will take... Does it require draining AC gas or removal of evaporator... Or it can be fixed easily ?

Thanks

Sandia man

I have been through this issue. The sensor is easily accessible through the top of the evaporator housing which resides under an easily removed plastic panel under the frunk near the wipers. Sorry I don’t recall the correct terminology. My compressor was cutting out at fairly high temps. I thought it was due to a defective sensor so changed sensors. The new sensor did the same thing. So the next thing I tried was covering the sensor in various ways to decrease its sensitivity. This didn’t work. I settled with leaving the sensor completely out of the evaporator housing so it’s not exposed to the low temperature in the housing. This worked well as compressor stopped cutting out at high temps. Be advised that this approach can leave the evaporator susceptible to freezing. I live in the desert so that has not been an issue. If you live in a high humidity region evaporator freezing could be a problem.

Dwad

Thankyou for your reply...I am living in gulf so desert area as well, your case is interesting one & you solved it, good to hear...( So your compressor was cutting off because your temperature sensor was reading low temperature & which was correct, now the function of evap sensor is to stop the evaporator from freezing as well but than why the housing temperature was going so low that the control unit was cutting the compressor off, sorry I want to know what was the real culprit in your case)
In my case AC was just never cooling, & through the test I confirmed that evaporator sensor is bad...
​​​​​​​

Sandia man

Since both the original and new sensors functioned the same, I assume that’s the way Porsche designed it to work. This is probably fine for temperate climates like Germany but not so good for the desert southwest US.
Since getting automotive AC advice from a retired psychiatrist is potentially dangerous, it would probably be a good idea if someone more knowledgeable like Tore Bergvill would comment.

911F1

Tons of knowledge here

https://rennlist.com/forums/993-foru...diagnosis.html

Dwad

Thankyou guys for your valuable comments....

geolab

it requires nothing with the AC, usually it reads 128* celcius stuck on that (when it's dead) , and that prevents AC compressor clutch to engage the compressor
You open your front trunk
stand on the passenger side beside the fusebox
to the rear of the trunk and left of the fusebox, there is a thick rubber strip holding a black plastic cover over the evaporator all along the back of the trunk
remove rubber strip and plastic cover
practically at 40% to middle of the car, you should locate the temperature sensor rectangular head, unplug it by pulling gently and take it out of its lodge,
liberate the cables connected to the sensor, because you need to cut the cables, and solder the new sensor cables , and introduce the new sensor , into the evaportator
solder and heat shrink for new sensor
voila

911F1

I just tested my evaporator temp sensor. My reading was 2.31 Kohms.
The complete a/c diagnostic thread mentions a reading between 3.3 - 7 Kohms
Doesn't seem to far off. What do you guys think?

https://rennlist.com/forums/993-foru...diagnosis.html

Dwad

While I checked my sensor resistance , I checked it for a temperature, mine was way off for ambient temperature (25-40 degree C) , so problem....
2.31k ohm could be the value for temperature less than 25 degree C, I believe.... So it should be ok...

957GT-YES

Pillow, Ha! Thanks again for the tip. The shop charges $190 to evacuate and recharge it. They can evacuate tomorrow morning and I can order parts and feel better about the birds and spotted owl. Funny that growing up we used to get rid of oil by digging a hole in our yard and pouring it in. Time marches on... I'll watch a couple of vids and read about how to change the compressor and figure I'll tackle it perhaps next week. It's getting warmer and my daughter will be gone for a week so I can hoon her X3 a big.

Cheers