Air Conditioner Clicking Noise and Not Cooling

: I hear this clicking noise under my hood when I am at a stop light or with the engine at idle. My air conditioner is not working as well as I remember it either. Are these items connected?

Howdy Carlos,

Yes, I think your two problems are related. The clicking noise you hear is the air conditioner compressor clutch clicking the compressor on and off too quickly, this is called short cycling.

The a/c compressor clutch is the round pulley looking part on the front of the a/c compressor that is attached to the fan belt. The compressor clutch is what engages the compressor and makes the air cold.

Short cycling can be caused by a few reasons which are:

1. The a/c system is low on Freon
2. There is a restriction in the a/c system and the pressure on the compressor is too high
3. There is a problem with the a/c compressor clutch or the compressor itself

I would have your mechanic hook up his a/c gauges and check the Freon level and pressures first, and top off with Freon if needed. You might only need a can of Freon to correct both the clicking and the poor performance problems.

If the system requires more than a can of Freon you probably have a Freon leak somewhere and your mechanic should perform a leak test to find the leak.

Austin Davis

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