My first annoying noise

[Color]

Had a lambda sonde replaced a couple of weeks ago under warranty, which also meant dismantling the exhaust system.
Since I got the car back, there is a new noise which is getting on my nerves. Especially since I've had a noise free car so far.

I sounds like a metallic rattle coming from the back of the car when I drive over a very bumpy surface, especially cobblestone covered streets. I already had the car in the garage again for them to check it out but they could not find anything.
So today I took a drive with a mechanic to show them the noise and of course then the noise was no more!! :x

Just one hour earlier it was there and quite persistent. :roll:
We did manage to produce one tiny rattle, but it was nowhere close to what I had experienced a little earlier that day. And I'm not turning insane, wife also hears it clearly.

So now I left the car at the garage and they will try to drive it again several times and see i they can reproduce the noise. But the mechanic hear the tiny rattle also so now at least he knows what to look for when they test drive later.

Anyway I wanted to ask if anybody else had a similar noise and if they ever figured out what the problem was??

 

[fire-n-ice]

Hi color, I'm afraid to say I've not ever had any noise for fear that the next time I drive it, I will find one , but I haven't. Can you make an appt. w/the dealership and just leave it there until they find and fix it? You'll maybe waste more time and gas going back and forth. Plus, you may get a hot loaner you drive like mad :evil: lol!!

 

[ovrkll]

Since the dealer was replacing parts near the exhaust system, I would say that a piece of heat shielding was moved enough to cause your rattle 8)

 

[Color]

Hi color, I'm afraid to say I've not ever had any noise for fear that the next time I drive it, I will find one , but I haven't. Can you make an appt. w/the dealership and just leave it there until they find and fix it? You'll maybe waste more time and gas going back and forth. Plus, you may get a hot loaner you drive like mad :evil: lol!!

Hi Fire-n-ice

Thanks for the input. It's already at the dealers and I told them to test drive it until they can find it. They are in for some fun at least

No loaner for me though, they don't to that here where I live, well, maybe if I asked nicely you never know. Anyway I got my daily driver so no big deal.

 

[Color]

Since the dealer was replacing parts near the exhaust system, I would say that a piece of heat shielding was moved enough to cause your rattle 8)

That's what I'm thinking also. The mechanic mentioned that they have to bend a little the heat shielding when dismantling the exhaust, so it might be that it was bended too little/much and as a result somewhere the exhaust touches the shielding when a bump rattles the exhaust around.

 

[Rick Hunter]

...So today I took a drive with a mechanic to show them the noise and of course then the noise was no more!! :x

Just one hour earlier it was there and quite persistent. :roll:

Do you think it may be due to seasonal climate? It is getting colder this time of year, and maybe the car's rattling until it gets warm?

 

[Adam D]

I'd put my money on a loose or misfitted exhaust head shield... on my last car I had a few fixings vibrate loose on the turbo elbow headshields which gave a metallic tinging rattle.

Easy fix, just replace the missing fixings or tighten and readjust the headshields.

Hope its something simple like that!

 

[Color]

...So today I took a drive with a mechanic to show them the noise and of course then the noise was no more!! :x

Just one hour earlier it was there and quite persistent. :roll:

Do you think it may be due to seasonal climate? It is getting colder this time of year, and maybe the car's rattling until it gets warm?

Could be, I did not have the impression there was a connection. I've heard the rattle on 'warm' days, 15 'C, after driving for an hour, but todays experience kinda gives the impression it's related to how warm the car is. Today was pretty cold, like 5'C in the morning when we took the car out. Anyway the noise did start immediately after getting the car back from the service, and there were no big change in temperature around that period.

Looking forward to hear from the dealers again. Anyway I don't think they mind having to test drive it. To my knowledge it is the only M roadster in the country, so I can imagine they don't get much of a chance to test drive one

 

[ovrkll]

Metal expands as it is heated, so the original theory of a heat shield being close/up against an exhaust pipe is looking better. Sure the dealer will find it after quite a few turns around the area

 

[Color]

Got the word from the dealer on friday. They detected the error and have corrected it. It was a heat shield that had been crumpled a little on installation and was touching other metal under the car. Very hard to detect it seems, as they had an inspection with no finds as mentioned earlier.
But anyway I'm impressed they persisted and found it.
Will have a dest drive next week to ok it, and we are back in business . .. or should I say, back in the garage for the winter

 

[Adam D]

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