I have a 98 Mercedes c230, the ac will work for about 5 minutes then warm air blow out, any idea what it might be?
Check the pressure on the high side(small coupling close to the compressor) this can be accomplished with a cheap arctic zone 134a refill kit. This will tell you if it is low on freon or pressures too high. If low, use refill kit to bring into range, if too high see a shop about proper vacuum down. If you recharge be careful about overfill it will cause high pressure switch to cut-off compressor.
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