Hi, I'm new to Porsche ownership. I bought a 96' 993 C2 in Feb off Rennlist. The car drives amazingly well. The A/C is problematic; looking through the forums here and at Pelican, I'm still unsure which parts need replacement.

1. Screeching noise: Sounds like a high-pitched cat or cricket on speed. It starts up after the A/C's been on for 5-10 minutes and seems loudest from the middle air vents. Not sure if it is a problem with the evaporator motors, or the blower in the engine compartment.

2. There are only two temperatures that the A/C puts out: cold or hot. If the control dial is turned to any setting above the coldest, then maximally hot air is vented. Is this a problem with the A/C control unit, or somewhere else?

3. There is an engine oil/gas smell that comes through the cabin when the A/C temp control dial is turned to any setting above the coldest level. Is this from an oil leak?

4. Finally, is this normal? A "fan" will turn on for short periods of time after the engine has been turned off (I hear it in parking lots when I return to the car, or in my garage). I can feel air coming from under the engine. As it's an air/oil cooled engine, there's no engine fan, but is there an oil cooling fan that comes on even if the car is turned off? Or does my car have ghost?

Thanks, Matt

 

Hi Matt, welcome as a 993 owner.
1: You may have a worn CCU fan, or maybe one or both of the main front fans are shot. (worn/dry bearings)
2: Clean the CCU air temp sensor
3: Oil/fuel smell in the engine compartment will be noticable when you get hot air from back there
4: Normal, it's the rear fan doing one of it's two jobs, cooling the heat exchangers when engine is not running
All details here:
www.porschehvac.bergvill.com
Cheers,
Tore

 

Hi Tore,
Thank you so much for your response and web link. I'm going to be studying your site. Wish I was in Oslo!
Matt