2002 with 4 cyl engine. While stopped and idling, the ac blows nice and cold. Low side line is cold and sweating good. But when i start driving it stops blowing cold air and blows not cold air. Has anyone had this problem before? I thought it may have been overcharged so i emptied the system and recharged with 24 ounces. But still the same.

 

Did you vacuum out the air? If not, that's your problem. Have to pull it down to -30 PSI for half an hour at least, to boil out any condensation as well. No atmosphere at all is allowed.

 

Yes. I pulled vacuum to 29 hg. Couldnt reach 30. Vacuum held overnight. So im im convinced no moisture and no leaks. Thanks for replying. I need all the help i can get. Lol

 

-29 hg converts to -14 PSI. Sorry, but we Yanks still use imperial measurements. If it held vacuum overnight that means no leaks which is good. The purpose of a vacuum is to eliminate all the air and boil out any condensation as air and moisture are not good for an A/C system, as you stated. When you are stopped, can you rev the motor up as if you are driving, and does the magnetic clutch for the A/C compressor engage at that RPM? Of course, this is with a charged system, not a vacuumed out A/C system.