... posted by Michael Smith  on Thursday, 8 March 2001, at 7:33 p.m.
 

                     Once again, the master manual writers have failed to define an element of my 1995 850 Turbo. I will
                     describe this element as best I can: It is cylindrical, appears to be a motorized valve, is located directly in
                     front of and slightly below the throttle plate cable pulley and has hoses which appear to bypass the
                     throttle plate. What is it?

                     My car is acting funny and this mystery element buzzes long after the key is removed. I do not think this
                     is normal. My “check engine” light has (once again) turned on.

                     Anyone know what I will have to do and how much it will cost for my beast to return to the road.

                     Mike

                     Sounds like the Idle Control Valve. How about a pic.
                     Sid

                     Michael-
                     I think you are refering to the IAC (Idle Control Valve), the device that sets the idle speed irregardless
                     of engine load. (Gear position, AC, ect) It is normal for it to hum for a short time after the engine is
                     switched off (maybe 10 seconds) because the control unit is still powered up after the key is switched
                     off.

                     Dave the Volvo Tech
                     '99 V70R AWD, '93 854 GLT, '82 242 DL

                     --
                     Dave the Volvo Tech