Ok my 97 caddy deville when the fan kicks on makes a pretty loud clicking noise. It only does it when i have the heat or a/c on. I thought it might be the fan clutch but im not for sure. Anybody have any ideas. Thanks

The engine cooling fans are electric. No viscous clutch. If one ticks, maybe a stick or wire tie has worked its way near one fan blade assembly.

If your HVAC blower fan is ticking at slow or medium speed, there's probably a leaf in the squirrel cage. Run it on High, recirc, and cycle the temp from cold to hot. That may loosen the offending noisemaker.

Last fall a friend up the road destroyed a 2 foot garter snake in the fan of his Chevy. Yuk.

Hey,
Maybe a squirrel in the cage. I agree, run it high and fling 'em out! K_C

Great reply guys. Anyways i think it might be my compressor.