BMW E39 HUMMING SOUND

ojola

I started and drove my 2001 E39 525i Tiptronic petrol car that has been garaged for the last 6 months. I noticed a loud unceasing humming sound coming from the engine cabin. Anybody experienced this? solutions please...

Nissan doctor

With respect, it will be impossible for anyone to offer a possible cause from such a vague description.

Is it louder when cold or warm, gets louder with revs or not, gets louder with speed or not, changes when in drive or neutral etc etc

ojola

Nissan doctor wrote: »

With respect, it will be impossible for anyone to offer a possible cause from such a vague description.

Is it louder when cold or warm, gets louder with revs or not, gets louder with speed or not, changes when in drive or neutral etc etc

Thanks for your interest; this noise i reckon stays same but gets drowned out when you rev the engine and as you drive the sound goes to the background. I would say it does not change. It is cold right now. Also the sound does not go away in neutral, reverse or when the car is idling. It only disappears when the emgine is turned off.

Nissan doctor

Have you opened the bonnet to try to narrow down the area that the noise is coming from?

swhyte027

Nissan doctor wrote: »

Have you opened the bonnet to try to narrow down the area that the noise is coming from?

Very vague discription but remove ur altenator belt and check your altenator pully and your water pump I'd say one of them are your culprits I've changed Afew of each on plenty of ocassions.then start your car with the fan belt removed to make sure the sound is gone.my guess will be that the noise will go with then change the required part.

Nissan doctor

swhyte027 wrote: »

Very vague discription but remove ur altenator belt and check your altenator pully and your water pump I'd say one of them are your culprits I've changed Afew of each on plenty of ocassions.then start your car with the fan belt removed to make sure the sound is gone.my guess will be that the noise will go with then change the required part.

I'd hazard a guess that its quite unlikely that the OP will be able to do much of that himself....

Tails142

Its all the one belt on an e39 anyhow.

swhyte027

Tails142 wrote: »

Its all the one belt on an e39 anyhow.

I'm well aware it's one belt that's y I've said remove the belt.well the op asked for advice and that's how to go about it.

rebel.ranter

At what speed does it start becoming more prevalent? Or does it make the sound when stationary?
Wheel bearings (comes as a single wheel hub part €252 plus VAT from dealer) are a common item to go but these will only make noise when moving, typically above 20mph.
Another possible cause while moving could be a defective tyre. My own e39 currently has this problem (need to order tyres for the front this week), it doesn't have to be worn beyond legal limit to be defective, mine isn't below the legal limit but is causing noise (my bearing just replaced under warranty on Friday).
It might be the brake pads lightly rubbing against the disc.....

It could be the water pump bearings (but you would need a new water pump if defective) if it makes the sound when stationary with engine running. It coudl also be the alternator bearings....
OP there are so many possibilities that without either a really good description of the characteristics of the sound or detail on what triggers the sound or a change in pitch of the sound it would be impossible to tell what's causing it.

swhyte027

I've stated all this.and from the ops post it's under the bonnet

Lucifer

Is the noise still there with your blower motor off? I have seen a few E39s where the fan motor got very noisey all of a sudden.