This is not your American cooling system. The AC compressor will cycle on/off to keep the compressor from heating up or hurting your mpg. Unfortunately, all of the cycling will wear on the compressor clutch (what you hear going 'click' when it engages) and the clutch will eventually have to be shimmed to reduce the gap.

You are also probably low on R134a, most of these systems leak a little.

My suggestion would be to shim the compressor clutch so its clearance is about .020, once it reaches .040 the gap becomes too great to work on a hot day. The DIY method is to glue plastic bread clips to the clutch anchors, I used folded pieces of thin metal with glue. It only takes a few minutes to do after the bottom air guide is removed and no jack required unless you have sport suspension.

Once the compressor clutch is shimmed to good specs, try the AC again. If the cycling is still too fast, add a can of R143a with the engine and AC running.

Klaus
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My name is Klaus and I am a V ♂ lv ♂ holic