I love it when I am asked if I am over 13 years old; with gray hair I don’t get carded anymore. Thanks guys for making it special to join CarTalk.

I have a '91 Honda Accord. When I turn the defrost on,the radio playing (I even noticed this happening listening to CarTalk), and the rear defrost on, the engine starts to make the sound–YEEeeEEeeEEeeEEeeEEee! I tightened the belt on the AC unit and the alternator, thinking that would stop it. It now makes the same sound except I can’t hear the radio it’s so loud. (I don’t want to miss your show.) Could it be something in the AC unit? The Alternator is fairly new.

I don’t think it’s the compressor. It’s sounds more like as a higher electrical load is impossed on the charging system it starts making this noise.

How old is the battery?


I bought the battery in November '08.


Have you tested the charging system?


Yes, I just went down to the auto supply store and had it checked out a few minutes ago. The battery has 650 cold cranking amps and 13 volts and the alternator was putting out 14 volts. The tech who checked it did told me that the sound seemed to come when the compressor clutch kicked in. Sounds like I need to replace the pump or clutch.

What happens if you turn on the defrost - and skip everything else?

If the defrost is on and nothing else is on, no sound.

Turn whatever you need to on to get the noise. Raise the hood, look, and listen. (Carefully - I hope needless to say. You either need a new belt or one of your pulley bearings is seizing up or your AC clutch is a mess. Whatever it is, it is the load that does it, and you tightening the belt increased the stress. Start narrowing it down.