when i got home from work today i left my car running and turned off the a/c, when i turned it back on there was a rattling sound for a few seconds and then went away. the rattling sound started as the compressor kicked on, there was a few seconds of delay from when i pressed the a/c botton until the compressor clutch kicked in, Bob
Is the A/C still working? If the A/C is still keeping the car cool, there is not a lot you can do about the noise. When the compressor is activated there will be some noise as it begins the compression / suction cycle. It is pretty much normal. The closed loop A/C system is maintenance free short of the belts and idlers. About the only thing you can do to the a/c system is add refrigerant to it, if necessary. The time delay that occurs from when the snowflake button is pushed until the compressor is kicked in is delayed reaction that happens as the climate controller processes the a/c request. The snowflake button is not a direct link to the compressor clutch. All it does is request the climate controller for A/C activation. The controller processes the request and then engages the A/C compressor, which takes a small amount of time. The controller is refered to as the IHKA in the Bentley manual. Hope this helps. Cheers!