Rattling noise in engine compartment - 986 Forum - The Community for Porsche Boxster & Cayman Owners

dittemore · 01-15-2006, 10:49 AM

Within the last 2 weeks, I have detected a "rattling noise" while at idle coming from the engine compartment. When I initiate the AC, the rattling noise is even more pronounced. Could this be bearing wearing out? Has anyone experienced the same thing. Any clues?

BrianD. · 01-15-2006, 11:43 AM

Try pushing in the clutch pedal. If the rattling goes away, it's loose springs in the clutch pressure plate. Worth looking into if you have a lot of miles on the clutch.

MNBoxster · 01-15-2006, 12:54 PM

Hi,

The List of Possibilities is nearly endless, especially in trying to diagnose it long-distance.

You will need to do some investigating on your own, or bring it to a shop. If you DIY, remove the front Engine Cover and get a Mechanic's Stethoscope (under $10). Then carefully move the probe around the front of the Motor paying particular attention to the Pulleys, especially the Idler Pulleys. Then take the appropriate remedies. Hope this helps...

Happy Motoring!... Jim'99

deliriousga · 01-15-2006, 05:34 PM

There are two things that caused rattling in my engine compartment while idling. First was the alternator pulley. Second were the idler pulleys. One way to tell if it's a pulley is to take the front engine cover off and use a mechanic's stethascope (sp?) to listen to each pulley and see if you can find the source of the noise.

Good luck!

01-15-2006, 06:47 PM

If it sounds a bit "tinny" it could also be a heat shroud. I have a noisy one that someday I'll tighten up.

steven · 01-16-2006, 01:17 AM

The pressure plate has no springs. The boxster has a dual mass flywheel made by Luk. Link for info http://luktest1.ina.com/content/en/products/dampers/zms_sv/zms_lv/zms_lv.jsp

I suspect mine is fuched as it rattles once the engine has warmed up, and goes away on engagement of the clutch... It sounds like ball bearing rattleing.

PorscheDoc · 01-16-2006, 06:38 AM

Pull off your top access panel, pull the front panel carpet, and then the front panel so you can see the serpentine belt. Start the car and see if you can pinpoint it. Keep clear of the belt though. If doesn't occur, then put the top access cover on and see if that causes it.