I have been trying to fix this forever.
And everyone that hears it usually just says my heatshield is rubbing somewhere but I have really tried everything with the shield, it isnt touching anywhere.
then! I found this video:

http://www.youtube.com/watch?v=hplEYmtjVUM

That is exactly what mine does, except mine seems to do it at low 2k rpms and just above and below 3k rpms.
It.. drives.. me.. crazy!

Mine seems to be more violent and bad sounding than the guy who posted that video, he posted two videos, the other i think you cant hear the rattle as much.
it sounds like it comes from like.. under the transmission? when I am in my car.

a lot of people seem to think it is an exhaust problem on his car.
do you guys think it could be an exhaust problem on mine?

he responded fast with to check my gaskets and from the other comments something with my resonator?

I want to see what you guys think.

Thank you sooo much, I want to get this fixed so bad.

Edit: I have a magnaflow catback, not alta.

 

Check if the underbody battery shield-type-thing is rattling off your exhaust. Im about to take that whole damn shield off its pissing me off cause of its rattling.

 

I had an Alta exhaust for 4k miles which is when the resonator came apart internally and caused all sorts of vibration. I too thought it was heatshielding but as soon as I took it off I lightly tapped it on the concrete and found it had a tambourine. So if its the identical sound then you may have a bad resonator.

 

Is that what yours sounded like, checkmate? (in the video)

Another thing i should have mentioned, it doesnt seem to do it right when I start the car, it does it after i drive for about.. 1 minute, maybe less.
seems to do it maybe a little more, maybe the same, in the cold.and I think I really notice it the most in gears 1-3, maybe 4 too.
Mine does seem to be louder than the one in that video, I might take my own video if i need to, its something i really want to get fixed!!

How much would a new resonator cost me if that is the problem?
Thanks.
Anyone with more info? =]

 

My (new to me) 2006 MC S has the same issue. It's all stock including the exhaust.

The resonance or vibration starts at about 2,000 RPM in any gear, peaks around 2,200 or 2,300 and seems to be gone around 3,000.

I also seems most noticeable when the engine is warmed up. It is hard to detect when the engine is cold.

It almost seems like a harmonic imbalance.

I e-mailed someone who had posted about this a few years ago an got this reply:

"No, the dealer claimed that "they all did it". I just learned to ignore it."

Since I bought mine used and the engine compartment was probably steam cleaned, it would be difficult to determine if the hydraulic motor mount has leaked out fluid. I wondered if this could be the problem.

Is there anyway to test the mount?

 

I just watched the video and that definitely sounds like an exhaust rattle of some sort.

I'm not sure that is the case with my car.

 

Yeah, but mine does it whether it is hot or cold really, and its just above 2k RPMs and then it doesnt really do it until i get to around 3k, in between mine doesnt do it as much, or hardly at all.
I would almost be willing to replace the whole exhaust system this annoys me so bad. haha.
(not that I want to spend that much $$$)

 

Get under it and hit the pipe with a rubber mallet. If it is in the pipe you should hear it.Usually what happens is if it is a double walled pipe the inner pipe has come loose and buzzes when the harmonics are right. If you can determine where in the pipe it has broken loose you can dimple the pipe with a blunt nosed punch in a few places and that will usually stop the buzz.

 

I wish it was that easy to just get under my car, haha.
I need to buy something to lift it up.

 

If you have the stock system you might want to check the pipe right after it exits the cat.On mine the weld wasn't good enough on the transition to the larger diameter about 4in from the flange.It seemed ok but for the black soot around the weld and then I noticed it slid back and forth,all of the weld bead was on the outer pipe.I welded it and it has been fine since.Looks can be decieving!

 

its definitely the resonator. get a replacement from Magnaflow or, if you want your exhaust louder and dont mind the drone, take the resonator off and put in a straight pipe. when you remove the resonator, stand it up and tap it on the ground, if you hear rattling, then there you go. Or, go under your car and with the palm of your hand or a rubber mallet, hit the resonator and listen for vibration and rattling.
-Andrew

 

It seems most logically the resonator, to get a replacement from magnaflow, they will charge me, right?
And if i took the resonator off and put in a straight pipe, is that legal?
I dont really know about these things.

Thanks!

 

i had the same exact rattle on mine. I have the magnaflow exhaust as well. There is a bracket that had came loose and the connection where the pipes meet had came loose so the pipe was hitting each other.

20 bucks at my mechanic to fix is with a new bracket. took 5 minutes

its not the heatshield like i thought it was at first.

 

Hmm, I need to find a way to get under my car, sometimes i wish it wasnt lowered.. haha.
Thanks for all the help! ill figure this all out soon.

 

I would just find a way to tighten it up somehow ( if possible ).

 

I had an Alta resonator rattle too. It grew worse over time. Since I was under warranty, they replaced it with their newly designed (and smaller) resonator and that took care of the problem. If you are under warranty or not, give them a call. If you are out of warranty I feel it is worth it to see what they charge for the new/smaller resonator.

 

My alta resonator took a dump about a month ago. I emailed the guys at alta and they really didn't put up much of a fight since it is less than a year old and i told them i'm a mechanic. Only problem is i've been waiting for the new one for almost a month and they tell me it won't be ready till the second week of may. I find it hard to believe that they don't have any on hand. soooo sick of that freakin noise

 

Yeah, I will call magnaflow today and see if they will help me out.
and yeah, that noise is the most annoying thing ever.
I hate when I am turning or something, and there is someone on the sidewalk, because I know my car just rattles on by, embarrassing.
I hope magnaflow will help me, but if not its not that big of a deal.
Cut, and weld it so it cant move inside, weld it back together.

 

Sorry it's taking so long, we haven't carried that exhaust for close to a year now, and we haven't made any parts for that exhaust in while! But we are making a few resonators, and they will be ready soon.

 

Here is an update.

I took the exhaust off, cut open the Resonator, to find that there was almost no stuffing in there, just a tiny amount of what looks like steel wool..
So, I packed it up full of Insulation, and welded it back up.
My exhaust note changed slightly, and the rattle/tinging is gone.
I am sooo happy that is over, and my exhaust sounds better now. a little deeper, I think I like it more now.

 

sorry to bump an old threadL

Im having a bit of a vibration issue with my Mini and I have an alta Exhaust.

The vibration sounds like the original youtube video and it vibrates around 2300rpm and around 3000rpm regardless of load on the engine. I notice it primarily when in a parking lot.

Has alta changed the design any?

 

If it'll make everyone feel better, I've got a loud, annoying rattle in my MILLTEK resonator (Lifetime guarantee). Been trying to work through the dealer (well-known here) but, apparently, they've turned a deaf ear (pun intended). I guess the "lifetime guarantee" is MY lifetime and they're waiting for me to die!

 

I ended up cutting my rather large/thick resonator out and welding in a smaller one that fits better. no more rattle!

 

My guys in our shop installed the newer ALTA Sport Tone exhaust after having run the Magnaflow for a while.

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I am really liking the growl the ALTA has, and the aggressive sound gets better with the more throttle you put down along with a jet blast sound like JCW exhaust has at WOT.

db5e4f54-7c3c-4289-ab5d-1aced81fda87.jpg?t=1373321301



Construction wise I noticed the hangars are different now. No longer do they have the round stock hooks welded directly to the pipes, instead it has a well made CNC hunk of steel welded to it, while the round stock slips through a hold down middle of it with locking bolt so the level of the system can now be adjusted.

The V-Band clamping system is top quality and what would be expected of a system costing much more. The techs commented on this clamping system and liked it very much.

Performance wise, the engine is breathing so much better now. I found shifting points and rev matching between gears to be better with less RMP drop off between gears. With the Magnaflow I had before, this 2003 MCS with higher gear ratios was comfortable cruising in 3rd, 4th and 5th in 3,900-4K RPM range before needing to upshift.

With the Alta's 2.5" piping, cruising in those same gears is more "comfortable" for the engine now at 4,000-4,200 RPM's. And the throttle response is much snappier too.

Current Set up:

JCW Tune by Kevin Dail
JCW 380'S
2 STEP COLDER NGK IRIDS
MSD PACK/WIRES
ALTA DFIC
ALTA V2.0 Intake with Lid
ALTA Version one 17% SCP
Stock Header/Cat - ( It's my DD )

So far really-really liking this exhaust