Let's Play "What's that Noise"! - 986 Forum - The Community for Porsche Boxster & Cayman Owners

crogers106 · 03-11-2012, 05:49 PM

I just picked my 2002 S up yesterday from the shop where it had been the past week. I had the LN IMS bearing installed, a new clutch, dual mass flywheel, RMS, spin-on oil filter adapter, magnetic drain plug etc.

Was so excited to get all this done and when I get home (100 miles away) I realize I now have this awful grinding sound which I think may actually be a vibration. It does it both when the car is in neutral and in gear and is noticeable when revving the engine and when driving - when I'm accelerating from a relatively low rpm.

It had NEVER done this before I just had this work done. I know I'll get answers from motor mounts to bad cats but I appreciate your feedback.

Here is the link to the audio clip. Listen carefully on the revs. http://dl.dropbox.com/u/54577550/Memo.m4a

Thanks!

K.Gaio · 03-11-2012, 07:25 PM

Interesting, Im currently having the same issue...had it up on a lift last week over at a muffler guy I use..mine sounds exactly like yours, we figured it was coming from the header/cats area. Im thinking bad cats myself. I would be interested in hearing what you find out about yours.

Krista

Brad Roberts · 03-11-2012, 08:40 PM

wow.. does sound like the cat came apart.. but "why" is the question. I'd be in the shops ass the next day telling them to come get the car (100miles)

Do they work on Boxster's regulary? Were there other Boxster's in the shop?

I have exploded cats in the past, but it was do to us playing with launch control

B

milliemax · 03-12-2012, 04:55 AM

To me, it sounds internal. In fact it sounds serious. Return the car to the mechanic today. Dont' drive it/have it delivered. Stop payment. I hope it is fixable. Also, where was the mike placed for recording ? Max

crogers106 · 03-12-2012, 05:07 AM

Thanks guys! I really do think it's the cats. When the car is turned off, I can bang on the cats with my palm and closely reproduce that same sound. I too am very curious as to why. Just drop a serious chunk of change to get the car ready for driving season and now it sounds awful. I'm afraid the shop is going to tell me it's just a coincidence they went out when they did and I really can't prove otherwise.

Brad, yes they are a German car specialty shop. Mostly BMWs there while I was in. I met the tech that worked on the car & he's owned 3 boxsters and has been through training with Jake Raby & Charles Navarro (that's what he said & I had no reason to doubt). I appreciate your input on this thread!!

milliemax · 03-12-2012, 05:13 AM

My cats are the same but I do not have that horrible noise . Only a slight rattle on cold start. Gone after warm. Like many others. Good luck.

crogers106 · 03-12-2012, 08:07 AM

After sending the audio clips to the shop, the Porsche tech and the shop foreman believe it's safe to drive. They say that it sounds like either the cats have come apart internally or more likely a weld on the exhaust heat shield has broken loose (since they had the tranny removed to do the IMS and clutch). I fear the worst - that it is the cats - which will be another grand to fix! While I guess I can't blame the shop, it seems like a strange coincidence they happen to give out the day I pick the car up from having all this work done.

jdiba · 03-12-2012, 08:16 AM

I hate that game !

Just makes me stressed !

landrovered · 03-12-2012, 10:27 AM

Bad cats sound like a tin can in a frying pan.

crogers106 · 03-12-2012, 11:59 AM

Quote:

Originally Posted by landrovered

Bad cats sound like a tin can in a frying pan.

Well that's about what it sounds like right now! Shop tells me regardless if it's heat shield or cats, they will take care of it! Feeling a lot better now....

Meir · 03-12-2012, 01:02 PM

considering the extensive repairs/mods they performed on your car, and assuming you paid for it (4k+ i would say? ) any respectable mechanic will fix it for you, especially you didn't have that issue before.

jsceash · 03-12-2012, 04:30 PM

You probably already checked this but it happened to me. Similar rattle was a loose O2 sensor. Rattled coming off the gas and a constant tick on the gas.

crogers106 · 03-12-2012, 05:10 PM

Quote:

Originally Posted by Meir

considering the extensive repairs/mods they performed on your car, and assuming you paid for it (4k+ i would say? ) any respectable mechanic will fix it for you, especially you didn't have that issue before.

You are right, close to $5K. I guess maybe I should expect it but to their credit they said they'll take care of it, even if it's cats.

Honestly, I didn't even touch the O2 sensors. I will check that before I take the car back to them tomorrow.

Thanks to all on this forum for comments and advice!!

tonycarreon · 03-12-2012, 05:23 PM

i had what i thought was a failed cat and/or heat shield last year. turned out to be a loose bolt on the alternator had worked loose and the sound was "traveling" down the pipes. have you had any work done on that? tightened it up and the noise went away.

crogers106 · 03-12-2012, 06:10 PM

Quote:

Originally Posted by tonycarreon

i had what i thought was a failed cat and/or heat shield last year. turned out to be a loose bolt on the alternator had worked loose and the sound was "traveling" down the pipes. have you had any work done on that? tightened it up and the noise went away.

I'm pretty sure all the work was done on the rear end side of the engine but you never know. When I bang on the cats with my palm, the sound reverberates down the pipes. It's going on the lift tomorrow - hope I don't have to leave it and I end up with an answer tomorrow.

Brad Roberts · 03-13-2012, 12:12 PM

The reason I asked about the number of Boxsters in the shop..

We label the parts as they come off each car so we don't mix up parts from different cars. We might have 3-4 cars with engines out at a time around here, and all the S stuff and 2.7 stuff is exactly the same. if we didn't label everything with the owners initials, it would end up all mixed up!!

Glad to hear they are stepping up. Heaven knows I have eaten the sh_t sandwhich on many occasions

Just part of doing business.

B

crogers106 · 03-13-2012, 04:54 PM

Well, got it on the lift today and all it turned out to be were two loose heat shields on the exhaust. Apparently this occurred when the exhaust was removed along with the transmission for the new clutch & IMS retrofit. I cannot believe that those heat shields made that kind of noise but now that they are fixed - sounds perfect!

As I mentioned, the IMS was upgraded to the LN bearing. Just for those that are interested - it's a 2002 S with 55K miles. The IMS was in perfect condition. Since I needed the clutch, I'm glad I went ahead and did the IMS though as for me, I'll sleep better.

This is the first time I've ever had to ask a technical question on this forum. I really appreciate those that took the time to respond. I felt much better and sounded knowledgeable when discussing possibilities with the shop. Thanks again!

Brad Roberts · 03-13-2012, 04:55 PM

Soo, did they not test drive it?

crogers106 · 03-13-2012, 05:12 PM

Quote:

Originally Posted by Brad Roberts

Soo, did they not test drive it?

Brad,

Yeah they did (about 15 miles) and I drive it home and didn't hear it either. With the top up and windows closed, you couldn't hear it. It wasn't until I got home and put the top down that I heard it. When they called me to come pick it up (the first time), they said the tech had just driven it and all was good. I don't know how a sound that loud couldn't be heard when it was buttoned up. I guess it's the brand new top.

milliemax · 03-14-2012, 04:11 AM

Sounded serious to me and that is why I asked where the mike was located for recording. Glad you have fixed the problem and it was not internal. Oil change next ?