986 Forum - The Community for Porsche Boxster & Cayman Owners - View Single Post

Steve Tinker · 12-25-2011, 02:20 PM

Sounds like your accessory belt / tensioner / idler rollers / water pump could be the cause.
Or it could be your AOS failing....

The easiest wat to check the accessories is to remove the belt and run the engine for no more than 30 - 40 seconds. If the noise goes away, closer inspections of the tensioning / idler roller bearings or water pump is in order.
Driving with a problem with any of the above is not a good idea.

Re the AOS, remove the oil fill screw cap and see if there is a suction - if the cap is difficult to remove, the AOS is failing.

12-25-2011, 02:20 PM	#3
Steve Tinker Registered User Join Date: Dec 2008 Location: Queensland, Australia Posts: 1,522	Sounds like your accessory belt / tensioner / idler rollers / water pump could be the cause. Or it could be your AOS failing.... The easiest wat to check the accessories is to remove the belt and run the engine for no more than 30 - 40 seconds. If the noise goes away, closer inspections of the tensioning / idler roller bearings or water pump is in order. Driving with a problem with any of the above is not a good idea. Re the AOS, remove the oil fill screw cap and see if there is a suction - if the cap is difficult to remove, the AOS is failing. __________________ 2001 Boxster S (triple black). Sleeping easier with LN Engineering/Flat 6 IMS upgrade, low temp thermostat & underspeed pulley. 2001 MV Agusta F4.