2000 s40 with 42k miles. Bought used and had lots of work done since getting it. When the AC is running it sometimes makes a hissing and gurgling sound much like coffee percolating.

Sounds like pressure building up up up...then sisssssss it is released. I am assuming it is the AC.

Any advice or suggestions appreciated. Love Volvo but this s40 has been a work in progress.

thank,

 

Be sure its coming from the AC but i had a problem with hissing noise and after ALOT of investigating its coming from wind whipping through the passenger side wing mirror...odd i know!!!

Im having problem with the variable timing valve making like a clucking noise from time to time....also finding a rattling/vibrating noise from the rear window (i think)

Any ideas please ?

Kind regards owner of a much loved Volvo S40

 

Thanks for reply. Mine is def from under the hood and it's when I activate the AC switch. It makes a sound like air being released from a pressure tank. Then some gurgling sounds and a repeat of the air escaping sounds. So no window leaks or leaves in the doors.

Had my VTiming value changed a while back. Lots of little issues that seem to be adding up in the $$$. But the car has under 45k miles so I guess it's worth investing the $ to keep it running.

Good luck.

 

could have air in the A.C. lines, fixing this would require a recharge by a professional