AC Refrigerant Pressures

I've searched, no luck. Does anyone have a specific AC refrigerant pressure chart for a 2003 Porsche 996? The essential 996 guide does not have a chart. Nor does the 101 projects. 101 projects says 25 to 45. That's a big range. The AC has never been opened. I just want to get a baseline of the pressures for future reference. Car is blowing cold and working as it should. Generic r134A charts show about 10 psi higher than the google AI search too for a 2003 Porsche 911. I would say the car was really hot being in the sun, black on black combined with only a 90 minute stop. Interior of the car was really hot when we got it and sat in traffic for 5 minutes right on start up. My black on black car was parked in the sun after a 2 hour drive. Stopped for lunch for 90 minutes. When I came back to it, temperature was around 100 degrees. Took about 15 minutes to cool the interior to a comfortable temperature.

U will want to use the temp charts for 134a. It doesnt matter what car/system its in.

25 min to cool down if the AC is �blowing cold� seems like an awful long time. Did you have it set to recirculate? The �cockpit� is pretty small volume wise - it shouldn�t take that long.

Quotes source post: 20643634

My daily is a new car Subaru Outback. yesterday, after being parked in the sun all, similar experience. really hot and muggy in the north - Toronto right now.

Pressures will vary greatly with Temperatures and fan speeds so is not the best indicator unless it is WAY out of range .. The best way to make sure the system is full is to empty it , then put in the EXACT amount prescribed... What is your pressures and are they WAY out of line ? IF the pressure is way low you can add a can and get CLOSE to the right amount and be COOL , ( yes I have done this many times and it works well in a pinch )

Pressure only tells a tiny bit of the story. With the type of system in VWAG cars the pressures will be in spec if there's anything from 10% to 200% of a full charge. By far the easiest way to check is to run the A/C on full power (max fan & low temp) when it's hot out with the doors open. Then feel or observe the suction line (large pipe) adjacent to the compressor. It should be cool and have condensation on it. If so system is as good as it can be.

So, I ordered 134 from the U.S. Had vent temps on a 90 degree day with windows down, sunroof open, parked in garage of 51degrees. Car had gone around the block. I hooked up the can at idle, added the 134. Got the low pressure up to 37 psi. Checked the vent temps and it was at 40degrees. I had weighed the can before adding the 134 to the car. Weighed the can afterwards. Only took 3.5 oz of the 134. At some point in the car's history, around 2015 prior to my ownership. The AC was inoperable. Service record showed it was a relay or some module. Not sure if the car was recharged at that point. So, I showed a 10% loss of 134 either in 10 years or from when my car was manufactured - 2003.

How long does it take to cool the car down now?

Quotes source post: 20650972

Pretty much the same as my daily. Although it was quite warm out, car was not heat soaked from being driven for a couple hours and sitting in a mall parking lot for another couple hours

I hooked a manifold gauge set to my AC when it was blowing barely cool to get a base line. The pressures were 30 Low and 70 High. I added R134a until I got cold air coming out and the measure was 35 Low and 160 High. Combined with doing the blend door foam fix, I now have great AC.