It drives fine, I am wondering if there is something like a bad CV joint or something else going on?
When coasting down the driveway, it was clanking but when I acclerate through the gears and reach highway speeds, it seems fine....

 

dealing with similar problem right now. in my case problem seems to be inside muffler, something has rusted or cracked loose. also check for cracks on exhaust.

 

968 premufflers, aka resonators, have a tendency to fail internally and make a loud annoying rattling. Basically, a metal baffle inside cracks and comes loose. This resonator is the part behind the cat but in front of the main muffler. On my car, I deleted it. If I could do it over, I'd put in a glasspack resonator from a name brand.

 

I have a B & B SS exhaust installed, I wish that was it. I'm going to mess around with the undercarriage and see if I can pinpoint it.

 

Give Dan a call at Exotic Motorwerks. Dan has been working on these cars for many years, is a straight up guy, and is located in Scottsdale (at the Airport). I've not had a bad experience with Dan nor have I heard of one. He has been working on my car for over 10 years (mostly with the previous owner who highly recommended EM).

 

I would be careful. If the car is running and is in neutral and you step on the clutch you have disengaged the running engine from the trans. At this point nothing in the trans should be moving. If there are trans issues the noises should stop.

 

Just had this issue with a 951. Got another transmission before it got bad. Noise is gone. Hopefully not much damage to the transmission.

 

My shop is in central phx if you want to throw it up on a lift. Would have to be after hours tues, thurs, fri

 

Bump for curiosity.

I would find some deserted hill and coast down it with the engine off, out of gear, then in all the gears with the clutch depressed. I like the song that the rotor lip sings but dread the parking brake spring popping off song.

My latest rattle was the anti icing hose at the throttle smacking the intake when the idle control would dip below 840...suspected the worst and it was the simplest thing.

 

That actually sounds like a worn cv joint or what would have been a bad u joint on a american car. Itr probably clanks on acceleration and also when you let off the gas, but when a constant pressure is applied (IE gas pedal) there is no noise.

I hope that is it as a lot less serious than actual trans issue.

New Guy

 

I have exactly the same symptoms as described.
Did you solve it?