A/C control unit issues

[SWFLHOMES]

Ok, it looks like I will need a trip to the dealer to diagnose my air conditioning issues. Is $150 US to test the system, charge the freon, check for leaks and scan the system fair? Also, it seems like it may be the control unit but I want to be sure. I am having the following issues:

1) When stopped at a traffic light the system will sometimes blow off freon. Seems to rise in temperature and build pressure (fan, contoller related or both?)

2) Right and left outside vents stop blowing any air when inside temperature is very hot.

3) Right side never gets as cold as the left.

4) Upper and lower vents will not blow air when switched on.

Can the controller cause all of these issues?

Thanks,

Craig

[deilenberger]

Probably not. The venting of freon means the pressure in the system is getting too high. Has it been worked on? Perhaps recharged without pulling a vacuum on it first? Moisture in the freon will cause this sort of behavior. Also - if the AC cooling fan (the smaller of the two) craps out, system pressure will get too hight.

[wvicary]

How do you know it's blowing off freon? If it's the high side pressure relief valve venting it makes one hell of a bang when it purges accompanied with a massive cloud of freon.