OverTake

Hi all. I had an issue not too long ago with the shift linkage of my 99 996 c2 breaking. I replaced it and all has been good. I was a total bum though and never reinstalled the center counsel or the e break. I want to say this recent problem started once I put the e-brake cable back on.

Whenever I let go of the accelerator there's a weird noise that sounds like cards hitting bicycle spokes starting at 3k rpm to about 1.8k rpm. If I push the clutch in the noise goes away. If I accelerate the noise goes away. This noise appears in all gears.

I called a shop that focuses on Porsche's in my area and they suggested it could be worn gear synchros or maybe my new shift linkage is rubbing against something. They said I'd have to bring it in for a diagnosis and they recomended having it towed. I've been driving it without any issues other than the noise. It's time to tack the problem. Any ideas? Thanks.

DBJoe996

Take the e-brake cable back off and see if the noise goes away. Might just narrow it down to something with the e-brake and the brake shoes inside of the rear rotors.

OverTake

Good idea Joe. Did just that and took her out for a spin. The noise is still going on. It seemed like maybe it was a little less pronounced, but it's still making noise btw 3-2k rpm. It's definitely a metallic like sound. It did go away momentarily at one point today but it was briefly.

DBJoe996

Well, hate to say it but from what you describe for when the noise happens (in all gears, clutch pedal in noise stops, accelerate and noise goes away) I'm thinking of the clutch pressure plate and/or clutch release bearing. The hard part of this problem noise is that it only occurs when the car is moving. Has the clutch ever been replaced? I would definitely get the shift linkage checked. And you may have to have a shop lift the car, start it up and engage the transmission while checking/listening underneath the car to pinpoint where the noise is coming from.

OverTake

Joe, if a clutch replacement will resolve this problem I'm actually quite relieved. When I bought the vehicle 2 years ago I found out that the individual who I purchased it from had the IMS bearing replaced, but decided to leave the clutch intact because there was 70% life left according to the mechanic. I spoke to the mechanic that did the work and he told me he still suggested that the guy change out the clutch because of its age. Anyways, upon returning home with the car I took it in for another look over and it was found that the clutch throw out bearing was bad (squeaking when engaged). I decided to live with it since the noise could mostly only be heard from outside the car. I was wanting to get a new clutch anyways at this point since I've driven the car pretty hard the last couple years and put an additional 20k miles on it and I'm sick of hearing the noise as well.

Does this extra information lead you to believe it is in fact an issue with the clutch? If so, will I be doing damage to any other components if I continue to drive the vehicle until I have a new clutch installed?

I really appreciate your insight Joe, thanks.

DBJoe996

Actually is does point to a problem with the clutch components. In my mind, any "metallic like sound" coming from the engine/transmission is cause for concern and needs to be investigated. Given the sounds/symptoms you have described, I would go straight to those clutch components. Will anything happen if you put a few more miles on it? Hmmm...that's a hard question to answer. Why gamble? It might leave you stranded somewhere, or at worst simply break altogether throwing shrapnel around in the bell housing, taking out other stuff. Sounds like you are loving the car and willing to get the clutch taken care of, so why not just do it? If the mechanic's information is anything to go on, I would just get it scheduled and get the job done. Get a new Dual Mass Flywheel, clutch and clutch plate, the upgraded bearing and arm, and a new slave cylinder...it will be all worth the cost of getting it all done at the same time. And give you peace of mind. Just my two cents....

OverTake

My neighbor does some work for a car shop down the street from us and he offered to introduce me to the owner and said they could probably put it on the hoist real quick. They sent me down the street to Leon's auto clinic and Leon got in the passenger seat to help diagnose the problem. When we got back to his shop he had me accelerate in neutral while he was behind the car. It was the muffler. He got in the car and accelerated and let the rps drop btw the 3-2k and the sound was 100% coming from the muffler. He told me not to worry about driving it and said to bring it in on Friday for further diagnosis.

Ever heard of this problem with the Porsche 996? Just glad it's not a transmission problem because I called around and got quotes between 2-3 grand. Also glad I haven't been damaging the vehicle by driving it. Maybe I'll have to get a new exhaust and this will be an excuse to get a nice sounding upgrade.

DBJoe996

Awesome! Glad I was wrong and you found your problem. And yes, it has been fairly common for an old muffler to break the internal baffles making a racket. It usually makes a buzzing/rattling sound. Glad you got it up on the lift and checked out.