My A/c will work for a few miles and then blow hot air. nothing will stop this until I turn off the ignition one notch and then back on (truck in neutral, coasting) and then it works fine all day.
Try replacing your cabin air filter. I know on some vehicles when they get dirty, it causes the A/C to to be intermittent. Here's a short how to video: http://m.youtube.com/watch?v=L37x4b35L8U
It is possibly just vacume line leak if it just doe,s it once in awhile.Check under dash at air box up to switch for leak,s.
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