My '04 MC 5sp has a weird resonance that I was wondering if anyone else has... let me describe it the best I can...

1- engine speed 2200rpm - 2400rpm
2- not road speed dependant
3- not gear dependant
4- does not occur when revving past the engine speed, only during cruise at that speed.

The resonance itself sounds somewhat exhaust related, but is not a vibration. It does not cause rattles or interior to buzz. I would best describe it as a hollow "howl".

There have been no modifications to the car, and it has no aftermarket equipment.

Anyone have this problem, or heard of it?

 

Sounds like you have a minor drone from the exhaust. If you are bothered by that, you should hear the Magnaflow

 

Yeah, I can imagine. I just started noticing it last week... though it might have been there since new. BTW... I forgot to list that the car only has 2000 miles on it. I also now have the dreaded "shifter rattle". UGH! :evil:

 

Try keeping the rpm"s around 2800-3500 when driving.
you may be lugging the engine running the revs so low.
Drop a gear and get your rpm's up. That would cause the dreaded
"shifter rattle " you describe
:smile:

 

--> yellocooper - I disagree on your RPM recommendations; 2200RPM is NOT "lugging" the engine. I cruise in 6th frequently above 1500RPM; this is the style I've found the MCS needs to boost its fuel economy, though keeping a higher RPM of over 2750RPM only effects mileage marginally. I would say cruising below 1500RPM is lugging it.

---> JD; Check your exhuast connections (or your dealership), or better yet; drive a fellow MINIac's with similar-to-more mileage, to see if you're just experiencing a "designed in" exhuast tone resonance.

 

I certainly agree that I am not lugging the engine. The sound is 4th gear and 40ish mph... and 5th gear at 54 mph are routine cruising speeds for me (hey, I live in Chicago...traffic sucks.)

Ryephile- I also agree that I may have a loose exhaust connection.

As for the shifter rattle, it happens mostly when starting out in 1st gear... it does not rattle once on the move.

 

Every once and a while I get exhaust drone like you are describing, normally (for me) it is 5th gear and 2200-2400 rpm. The times that it has been really noticable is when it is raining. I know that sounds weird but that is just what has happened, conincidence or not. I have tried to make it do it on command to no sucess so I am not worried that it is a problem, rather it is just the way the car is. I have had it when I can FEEL the drone through my seat, I think it is cool actually (but it would get old). By the way, my car is stock mechanically.

_________________
2003 DS/W MCS with white stripes and white 17" Team Dynamic Pro Race 1's. MOTOR ON!!

 

That is why I am concerned... if there is a problem I want to have it fixed... if it is just "how the car is" then I can deal with it. I guess the next step is visiting the dealer... ugh!

 

Interesting Npartist mentioned 5th gear. Over the last couple weeks, I have noticed a vibration or some type of resonance that I can feel everytime I go to fifth gear and at 42 MPH. The feel is similar to a flat spotted tire, and you can kind of hear it too. But if I coast out of gear at 42 it feels smooth. It only occurs with slight accelerator pressure. Off the gas, or heavy on the gas and there is no problem. I did install 4 snow tires in January, but I would think I would feel that in every gear if it was tire related, and I do have an aftermarket exhaust. Yesterday I ordered some exhaust band straps to seal the connections in case that is the problem. Once I change the tires back out to stock, if it is still there, I have it looked at. If anybody has any other suggestions, please chime in.

 

a "drone" at that RPM is totally normal, and it is even bigger on the '05 . The exhaust is just built to resonate that way, and it happens on every MINI.

-Paul

 

I had a sound like the one you describe and I was sure it had something to do with the exhaust system like the exhaust pipe vibrating or rubbing up against something.

When I took it in to the shop, they discovered that the sound was caused by a cracked air intake box of all things! The box was replaced and the sound went away.