A/C Troubleshooting

[cjr]

Hey, all
After spending several hours chasing links and youtube videos, I brok down and called my mechanic about my A/C. Mechanic says he's taking appointments, only, and is booked out to July.

So.

I have a 2010 E61. 110k miles. Air conditioning blows ambient temperature air.

I checked the iDrive vent setting, that's on full cold. No change.

I hooked up an A/C low and high pressure manifold gauges.
With car off, pressure on high and low is about 85-90psi.
With car running and AC on, low is about 25 psi, high is about 150 psi.

I got some R134a, and tried to charge the system. Refrigerant did not go into the system. The canister did not lose weight, and the canister did not cool off.

Side note- For a few weeks, the car is running a bit hot. Engine coolant temp is usually rock steady around 210F, but lately it seems to be fluctuating a bit between 210F-219F. It usually flits on the low side of that, but doe sometimes get up to 219F, especially in city, stop and go driving. Yes, I know it's designed for that, but it is unusual. Checking at idle last night, the radiator fan seemed a bit, um, unimpressive. It turned on at about 217, but was kind of hesitant. It eventually blew okay.

I found the AUC sensor check, and that did not seem to do anything.

I have a code reader, but there were no codes.

Any thoughts? Ideas? Recommendations?

Thanks in advance

[mobitechaz]

Your freon pressures are too low, assuming you are in a warm climate requiring A/C. Pressures should be around 30 low side, and 180-200 high side. I would check to make sure you're guages are working properly. Freon added through the low side port. Test flow with guage disconnected to hear if gas is coming out of your guage. Then reconnect gauge. If you don't have a sight glass which allows you to see the flow of freon which condenses in the sight glass and forms a liquid gas level line, than best way to is feel the grenade or whatever tank you're using. it should be getting cold as freon is being pulled out (as gas in tank expands, endothermic rxn=cold). Other possibility is the the valve on your low pressure A/C line is stuck. Buy a shraeder valve removal tool and watch a quick DIY video on how to do it. (NOTE: you'll need to evacuate your freon beforehand). If you don't have a freon evacuator, best to schedule an appt with a local shop , they will pull it out, and put it right back in with their machine. don't let them charge you for the freon. once gas is evacuated, change out the shraeder valve, and then have them vacuum the systm and recharge it with what they evacuated. you can then top it off yourself. and bring your low pressure side to spec. you should let them know that your shrader may be stuck because the'yll need to evacuate it solely throught the high pressure side in that case.