A/C High Speed Fan

So when I'm sitting still, in traffic for example, on a warm day with the A/C on, it doesn't stay cold. I took it in in last July to have them add oil to the compressor and add freon to the system since I had just replace all of the A/C parts and wanted to be sure everything was filled properly. Now one day last summer it was a little over 90 degrees and the air was basically useless. I have only heard the A/C fan kick into high speed while I sat still a few times, and I think I read that it won't kick on until the freon running through the condenser hits at least 200 some degrees. But even when that fan kicked into high speed, it was only on for a few seconds and the air didn't have a chance to get much cooler. I tested the high speed fan relay and it went into high speed, but at the same time the fan that cools the engine shut off. Is there something amiss? Is this normal? What do I do?

Check the connector to the radiator fan. Mine burned up, causing erratic fan operation. It caused the A/C to be useless & the engine to overheat in traffic. I cut the plug out & soldered the wires together. No more problems.

Update: I replaced the relay and now, when the high speed fan turns on, the air stays cold and the fan keeps cycling on and off as normal. HOWEVER, in order to get the fan to turn on in the first place, the car has to be at idle for nearly ten minutes. I let it sit in the driveway on a hot day and it kept the air cool, but I was stuck waiting for a train to pass and the fan never kicked on, so the air gradually got warmer and warmer until it became uncomfortable. On many cars, I hear the fan turn onto high far more frequently, and I want to know why mine is being so conservative with the fan.

Are you talking about the radiator fan?

Nope, the condenser fan. The big one on the drivers side.