strange rattle sound on slow pull off. E46 330i

osiris

///Member
Hey,

It's been a while since I have posted anything on my 2004 E46 330i, I honestly haven't had any issues with the car since I have had it however at the moment as my thread title states, when I pull off slowly I hear a funny rattling sound, almost a metal on metal sound. If I could describe it, it sounds almost like a desk fans metal blades touching the protective caging when you pick it up and move it too fast causing it to fight its centrifugal force.

Now I know that my control arm bushes are shot and need replacing, I will do that as soon as I get a chance to pull in somewhere to get it done. Could that be the problem?
The car is a 6 speed manual so has no viscous fan so I ruled that out.

Another thing I noticed is that if I accelerate hard, when the revs go past 4k rpm I start hearing a bit of a squealing sound, could this be a belt or is it my clutch? I have never heard of a clutch making a noise and it doesn't seem to be slipping so I am not sure what this is.
 

Yuben

Senior Moderator
Staff member
My guess is to check the 3 pulleys as well as the caliper clips on the brakes.
 

beezo003

New member
Im sure i also got that same sound also been trying to figure out what it is.

Mainly Only when pulling off, once going it goes away?
 

Lizzard

Active member
Idler pulley, check this out. Had almost the same sound and you could only hear it when pulling away and then it was gone (presume that 6 cylinder symphony over wells the sound).

But look at the idler pulley, it packed up on our way to a resort and ended up towing it back home.
 

kilotango

New member
if its a loud metallic sound thats coming from underneath the car, it could be the exhaust being loose or touching something.

last year i was parking at a shopping centre and went over a speed hump while turning. there was a huge knock..and an exhaust bracket about halfway of the car bent upwards which was hitting the exhaust. made a really shitty metallic rattle when accelerating.

i took it to a place that does wheel alignment so i could use their ramp and then found that the bracket was the problem when i shook the exhaust. you could have something similar...or somehow exhaust related if the sound is coming from down below
 

iambengiey

New member
osiris said:
Hey,

It's been a while since I have posted anything on my 2004 E46 330i, I honestly haven't had any issues with the car since I have had it however at the moment as my thread title states, when I pull off slowly I hear a funny rattling sound, almost a metal on metal sound. If I could describe it, it sounds almost like a desk fans metal blades touching the protective caging when you pick it up and move it too fast causing it to fight its centrifugal force.

Now I know that my control arm bushes are shot and need replacing, I will do that as soon as I get a chance to pull in somewhere to get it done. Could that be the problem?
The car is a 6 speed manual so has no viscous fan so I ruled that out.

Another thing I noticed is that if I accelerate hard, when the revs go past 4k rpm I start hearing a bit of a squealing sound, could this be a belt or is it my clutch? I have never heard of a clutch making a noise and it doesn't seem to be slipping so I am not sure what this is.

For the squealing sound replace your belts. I think they should routinely be changed every 90000k's not really sure. But give it a try.
 

osiris

///Member
Cool thanks for all the help guys, I have some stuff to check out now :)
It could very well be a loose exhaust bracket perhaps so maybe on Saturday I will get it on a lift and check it out.

Idler pully is probably also something I should check out along with the belts just for preventative maintenance.

Thanks again guys.
 

M135i

Well-known member
Sometimes could be as simple as a heatshield hitting the exhaust or similar?
 

osiris

///Member
Replaced the idler pulley and the squealing sound it was making at high rpm is now gone.

Problem 1 solved :)

the rattle still needs to be sorted but haven't had a chance to get it on a lift so will update when I get that checked out.
 

moranor@axis

///Member
Official Advertiser
if you can feel the vibration in the gear knob it is probably your flex disk that is torn and can now knock the gear linkage under heavy load
 

AudiDriver

Active member
Rattling sound on idle and pullaway turned out to be the gearbox input shaft bearing on my S4. Of course that would go away when the clutch was depressed with the car stationary.
 

Serg_ZA

Member
moranor@axis said:
if you can feel the vibration in the gear knob it is probably your flex disk that is torn and can now knock the gear linkage under heavy load

What are the rough prices of those two parts?
 

nirvash

Well-known member
Also check your sway bar links, if loose they can make that metallic knock/rattle sounds, happened on my old 330i
Good luck
 

moranor@axis

///Member
Official Advertiser
Serg_ZA said:
moranor@axis said:
if you can feel the vibration in the gear knob it is probably your flex disk that is torn and can now knock the gear linkage under heavy load

What are the rough prices of those two parts?

PM pop me your vin the e46 has a different flex disk depending on engine and gearbox
 

osiris

///Member
Ok so I replaced the control arm bushes now, Damn what a flipping difference that made to my car, I put new front tires and got the alignment done after the control arm bushes were fitted, this honestly feels like a new car now. My control arm bushes were screwed. :skit:

I still haven't found out what the rattle on pull off is, but its not on idle, that was the idle control pulley, however on very slow pull off it is there and it definitely sounds like a loose exhaust mount, I need to get under this car and have a look.

Other than that, the car is now running like a dream, my alignment was heavily out because they couldn't set it due to my control arm bushes.
 
Top