transmission or exhaust system?

[dezpimpdada]

hi all, my 02 boxster S 6 speed with 80k miles has been having vibrating metal hitting noise. first thougth is loose parts in the exhaust system ( heat shield, cat. convertr, etc). it is ongoing for the pass 20k miles i never really look into it too much, until one day i decided to take it to Midas. the guy showed me with the car lifted the source of noise and thinks its coming from the transmission. with the car at idle, i hear from the transmission area metal grinding/ rotary sound, but this is differrent than when the engine is ravved up the vibrating metal noise becomes very noticeable. if i drive in the alley or somewhere that creates echos, you can really hear the noise. its mostly in 1st and 2nd gear at start up or on reverse, also louder with higher rpm at idle or taking off. a local shop shows me a loose arm/bar attached to the outer trasmission next to the muffler and thinks that's part of the problem. he suggested the only way to fix that is a new transmission but its ok to drive the car.

i have the clutch replaced at 32k miles now its at 80k but it still drives fine. no problem with changing gears or any unusual feelings when driving the car. i have an appointment with a porsche guy this week but would like to know if i can get some info regarding this or if anyone's having the same problem.

[Stefan]

I'm betting the problem is the forward heat shields, which are on either side of the transmission. These things are hard to pinpoint by ear. I doubt the problem is the transmission itself.

[Beelzy]

I would tend to agree.

IMO, Porsche trannys don't grind up, they blow up. ^_^

[dezpimpdada]

updates

i have the car looked at on saturday and was told it is not likely the tranny. maybe the heat shield or bad cat. i am hoping its not the cat because i had just passed 80k miles for the emissions warranty limit. loose heat shields i can deal with. i am bringing the car to dealership next week for a " better" diagnostic. ^_^

[angelina]

updates

i have the car looked at on saturday and was told it is not likely the tranny. maybe the heat shield or bad cat. i am hoping its not the cat because i had just passed 80k miles for the emissions warranty limit. loose heat shields i can deal with. i am bringing the car to dealership next week for a " better" diagnostic. ^_^

Take a rubber mallet and crawl underneath the car, tap everywhere and see if you can get a rattle

[secretagent214]

I had a problem a while back that sounds similar. I had a metallic rattle from the right rear of the car whenever I accelerated hard or for a second after I let off the gas pedal quickly. I had a really hard time locating the source. I tapped with a rubber hammer all over the exhaust and checked the tightness of all the bolts. I even took off the cat and muffler and checked them. I wasn't having any luck, and I decided to put that problem on the back burner to focus on my noisy rear suspension.

Focusing on that led to the solution to the exhaust problem, in a round about way.

I took it to a service station that specializes in Porsches and BMWs and asked them to just identify a bumping noise from my rear suspension over rough pavement (which I identified myself later to be the track arm ball joints). They called about an hour after I dropped it off and told me they identified it and went ahead and fixed it since they were there and didn't require any parts. They told me it was a misaligned exhaust system. They didn't charge much. They did nothing for the bumping noise, but I was happy to have the exhaust noise gone :)

Edited July 31, 2008 by secretagent214

[fredkhaz]

hi all, my 02 boxster S 6 speed with 80k miles has been having vibrating metal hitting noise. first thougth is loose parts in the exhaust system ( heat shield, cat. convertr, etc). it is ongoing for the pass 20k miles i never really look into it too much, until one day i decided to take it to Midas. the guy showed me with the car lifted the source of noise and thinks its coming from the transmission. with the car at idle, i hear from the transmission area metal grinding/ rotary sound, but this is differrent than when the engine is ravved up the vibrating metal noise becomes very noticeable. if i drive in the alley or somewhere that creates echos, you can really hear the noise. its mostly in 1st and 2nd gear at start up or on reverse, also louder with higher rpm at idle or taking off. a local shop shows me a loose arm/bar attached to the outer trasmission next to the muffler and thinks that's part of the problem. he suggested the only way to fix that is a new transmission but its ok to drive the car.

i have the clutch replaced at 32k miles now its at 80k but it still drives fine. no problem with changing gears or any unusual feelings when driving the car. i have an appointment with a porsche guy this week but would like to know if i can get some info regarding this or if anyone's having the same problem.

Hello,

I have a 996 see if this info helps.

http://www.renntech.org/forums/index.php?s...c=19086&hl=

Edited August 1, 2008 by fredkhaz