Strange rattle / metal shaking sound 99 Boxster - 986 Forum - The Community for Porsche Boxster & Cayman Owners

audisnawb · 04-15-2013, 04:22 AM

Hey Guys,

The past couple weeks my car has been making a strange rattling sound (thats the best I can describe it). I could have sworn it was the heat sheild for the exhaust, but I brought it to a local shop real quick and it all checked out.

It sounds like marbels in a tin can or sheet metal rattling. My initial thought was IMS BEARING, however, it comes from the front area of the car... the engine purrs, no ill sounds at all... so it has to be the heat shield, right? It only is noticable when in low gears and accelerating. It is quiet in 4th and 5th gear and on the freeway.

Maybe I should bring it for a second opinion....

Any thoughts?

Joe B · 04-15-2013, 05:27 AM

You sure it's not a rock stuck on a brake pad? Mine sounded like that until the rock fell out. Does it do it at a standstill?

Nimbus117 · 04-15-2013, 06:56 AM

Mine did this but the rattling was from the rear of the car, the two lambda probes on the LH exhaust were lose and rattled on acceleration/deceleration. At steady throttle there was no rattle. I could only hear it when going less than 30 in low gears as road noise drowned it out going faster.

HAUSIDMT · 04-15-2013, 08:47 AM

In my case it was a tin sounding rattle that was low RPM dependent, on my way to work. Then BOOM tossed the water pump. No matter what it is check it out, try pulling the covers off and see if it is coming from the front of the motor, even checking for play in the water pump pulley. If any have it towed don't risk driving then losing the water pump.

I'm no mechanic, but just sharing my experience with a similar sound.

audisnawb · 04-17-2013, 09:18 AM

Quote:

Originally Posted by Nimbus117

Mine did this but the rattling was from the rear of the car, the two lambda probes on the LH exhaust were lose and rattled on acceleration/deceleration. At steady throttle there was no rattle. I could only hear it when going less than 30 in low gears as road noise drowned it out going faster.

Hi Nimbus,

Your situation sounds exactly like mine. Its in a local Porsche specialist shop as we speak. He said I have a couple small exhaust leaks as well as need some things "tightened up" under there. Ill give you guys the more technical information when I pick the car up tonight.

Cory

audisnawb · 04-17-2013, 01:13 PM

OK,

So I talked to them, they pulled the entire exhaust and found a few leaks they fixed for me, replaced ALL heat sheild bolts. They said it was providing the majority of the loud noise and rattling. They also replaced two exhaust clamps. The bill seemed quite steep tp me though..... 2.5 hours of labor and the clamps was $348.00...? If I had known that I would have put a new exhaust on.....

Ah the joys of being a European car owner.

audisnawb · 04-18-2013, 12:09 PM

Well Im pretty aggravated! I picked my car up last night and the noise is still there, and seems louder than before! It may seem louder because they made the exhaust quieter by fixing the leak.... They want me to bring it back in for some more evaluation. It stinks being in this situation. I just spend 350 dollars for nothing.....

don330 · 11-15-2014, 12:19 PM

Did you ever figure out what the problem was? My Boxster has been making this noise on acceleration at low speeds for quite some time now. It's been in for service and my mechanic hasn't picked up on anything. It doesn't seem like anything major but the noise is annoying.

Reebuck1 · 11-15-2014, 05:37 PM

Had a similar problem with my 1999 C4. Ended up banging on the heat shields on the exhaust manifolds and it fixed the problem. You have something like it on your exhaust just in front of the CAT. It is welded to the pipe in front of the CAT. It could be source of the rattle.

apatt · 11-24-2014, 10:25 AM

Quote:

Originally Posted by don330

Did you ever figure out what the problem was? My Boxster has been making this noise on acceleration at low speeds for quite some time now. It's been in for service and my mechanic hasn't picked up on anything. It doesn't seem like anything major but the noise is annoying.

Had the same problem, sounded like a can with marbles rattling around coming from the rear of the car when driving at low speed on cobbled roads, turned out it was the rear track control arm. Got it sorted and its fine now, this is apparently a wear and tear item which is a common issue with cars that are getting on now. Best of luck!

Viper10000 · 11-24-2014, 03:18 PM

I had a similar sounding problem. I removed the rear cats and put in bypass pipes, no more noise. Mine is a 2002 2.7L