[popvictorcosmin]

Dear bimmers,

I own a 428i with the N20 engine with 80k km on the clock which I purchased new from BMW dealership.

To this day I have not made any single modification (interior or exterior), no tuning whatsoever, basically the car is stock and every bit and bolt is OEM. It hasn't been involved in any crash except for the unavoidable scratches and bumps from (other) idiot drivers who can't park.

Problem is for quite some time now I've been hearing a faint whine coming from the engine and lately it has intensified. The whine I'm hearing goes up and down with the revs, and you can clearly hear it between 1 and 2.000 rpm. Afterwards the noise from the turbo pretty much covers the whine sound.

You can hear me explain here:
https://files.fm/u/3d8hd9vf

I've checked:

- timing belt and transmission
- turbo
- serpentine belt (including alternator)

Nobody seems to have a clue as to what the source might be, but it's becoming annoying and increasingly scary as to what might follow.

I've recently came up with the idea that it might be the damned power steering belt but... it's electric, so it can't be that.

Any of you guys ever heard anything like this? What was the source and fix?

Thanks

[Billfitz]

An error occurred during a connection to files.fm. SSL received a record that exceeded the maximum permissible length. Error code: SSL_ERROR_RX_RECORD_TOO_LONG

[328iX]

Have you checked for any diagnostic codes? Have you had a dealership look at it? Worst case scenario if it’s something bad it will eventually get bad enough to where you can pinpoint it easily and hopefully you’ll still be warrantied

[popvictorcosmin]

Originally Posted by 328dX

Have you checked for any diagnostic codes? Have you had a dealership look at it? Worst case scenario if it’s something bad it will eventually get bad enough to where you can pinpoint it easily and hopefully you’ll still be warrantied

Obviously the first thing I did was go to BMW and had the car checked. No error code showed up, nor have I gotten anything from the car's dashboard. Basically I'm in the blind & the car works like new but... There's this super annoying sound.

[popvictorcosmin]

Originally Posted by Billfitz

An error occurred during a connection to files.fm. SSL received a record that exceeded the maximum permissible length. Error code: SSL_ERROR_RX_RECORD_TOO_LONG

That's weird. I can very easily listen to the recording even from the specified link.

[328iX]

Originally Posted by popvictorcosmin

That's weird. I can very easily listen to the recording even from the specified link.

I don't want to download anything but if you put it on youtube ill listen

Usually a whine can be from a pulley or even your alternator, try removing the accessory belt and seeing if it goes away but i see you already checked the key things.

[popvictorcosmin]

Here is a youtube link to the same audio file in case any of you were scared the initial link was a scam or something.

[sspade]

I hear it.

Sounds like possible timing chain failure whine.

What was your oil change interval for these first 80k km?

Have you used Auto Start/Stop feature regularly since new?

[popvictorcosmin]

Originally Posted by sspade

I hear it.

Sounds like possible timing chain failure whine.

What was your oil change interval for these first 80k km?

Have you used Auto Start/Stop feature regularly since new?

Oddly enough the timing chain was my initial thought and went to BMW Service for an inspection after reading that the N20 engines have had a factory recall for this problem. They said it's in perfect condition, however I have my doubts it is so.

Though why would the timing chain produce such a high pitched sound? Chains should rattle, not whine, as far as I can imagine. I'm no expert in car mechanics.

I've used Start Stop as less often as I could remember it was on but always turned it off for being annoying.

Oil change every ~15.000 km.

[Billfitz]

That sounds like the timing chain. There are more than a few threads about the problem, including videos that sound just like yours.

[popvictorcosmin]

Originally Posted by Billfitz

That sounds like the timing chain. There are more than a few threads about the problem, including videos that sound just like yours.

I wouldn't be asking this question if I haven't watched and read most of them, but BMW Service said that the Timing Chain is in perfect shape. It baffles my mind to think that BMW Service would say it's in perfect shape if it clearly isn't so.

[sspade]

Timing chain begins to whine as it works (burns) a groove into the plastic guides. This will continue until the guides snap.

Have you checked the chain for slack? Turn off engine and inspect chain visually and manually through oil fill hole on top of crank case.

Take a pic and report back.

[Billfitz]

Originally Posted by popvictorcosmin

It baffles my mind to think that BMW Service would say it's in perfect shape if it clearly isn't so.

Experience tells us that it wouldn't be the first time, to say the least.

[cfm56d7b]

Did the dealer provide any specific feedback about the noise itself regardless of the root cause? The first step is to acknowledge that the noise is abnormal. That's the dealer's responsibility. The second step is to determine the cost of finding the root cause. The decision to proceed and pay for the diagnostics is entirely yours.

I also suspect that the problem could be with the timing chain and the tensioner.

[bavarianride]

To OP, do u have access to the shop foreman in Romania dealer?

Those foremen(at our local dealers) are the top technical guys in each dealer and usually are quite capable and neutral.

Do ask politely to talk to foreman and ask him to listen to the engine while u rev(can be done just at service driveway).

[popvictorcosmin]

Originally Posted by bavarianride

To OP, do u have access to the shop foreman in Romania dealer?

Those foremen(at our local dealers) are the top technical guys in each dealer and usually are quite capable and neutral.

Do ask politely to talk to foreman and ask him to listen to the engine while u rev(can be done just at service driveway).

Yes I do. First thing tomorrow morning I'll pay them a visit. I already sent an email to BMW Romania giving them a detailed explanation of my situation, hoping that they will "urge" the local dealership to take the matter seriously. I'll be back with more info tomorrow, hopefully without too bad news.

[popvictorcosmin]

Originally Posted by cfm56d7b

Did the dealer provide any specific feedback about the noise itself regardless of the root cause? The first step is to acknowledge that the noise is abnormal. That's the dealer's responsibility. The second step is to determine the cost of finding the root cause. The decision to proceed and pay for the diagnostics is entirely yours.

I also suspect that the problem could be with the timing chain and the tensioner.

The dealer said the sound is normal on a cold engine, coming from a valve (?) on the turbo. Unfortunately the sound is persistent on a warm engine... What they did was blow me off. That's what they did.

[328iX]

It has to be the chain, or a pulley, alternator or belt etc. If the sound is increasing with revs 9/10 times it's one of those.

I don't see why they would deny the issue if the sound is very audible and you cannot argue with that.

They are either lying, or being cheap and don't want to do the work. Escalate the situation to your corporate offices or managers. It almost sounds like a supercharger and they say it's normal? hahaha what a joke. Best of luck.

[sspade]

Inspect the chain for slack. Put your fingers through the oil fill hole *** with the engine off*** and lightly put both upward and sideways tensions on the chain. Is there any movement?

Take a photo with smartphone and post for the group (of the chain, through the oil fill hole). A photo may reveal if there is any scoring on the chain.

To be honest - my N26 (2014) has a bit of scoring visible on the chain. I think a lot of ours do. This may or may not be related to failure.

Play in the chain however may indicate that the guides are failing as they are plastic.

[Billfitz]

That's not turbo noise. Your dealer either doesn't know what he's doing or he's feeding you a line of bullcrap. How far is it for you to drive to Munich?

[popvictorcosmin]

Originally Posted by Billfitz

That's not turbo noise. Your dealer either doesn't know what he's doing or he's feeding you a line of bullcrap. How far is it for you to drive to Munich?

About 11 hours of driving, not far. However my wife's nephew works in Vienna as a mechanic at Ferrari and said he could try and help me with a check up for free at their service, but Munich would be my first choice...

[popvictorcosmin]

Originally Posted by sspade

Inspect the chain for slack. Put your fingers through the oil fill hole *** with the engine off*** and lightly put both upward and sideways tensions on the chain. Is there any movement?

Take a photo with smartphone and post for the group (of the chain, through the oil fill hole). A photo may reveal if there is any scoring on the chain.

To be honest - my N26 (2014) has a bit of scoring visible on the chain. I think a lot of ours do. This may or may not be related to failure.

Play in the chain however may indicate that the guides are failing as they are plastic.

I'm guessing to do the procedure from underneath the car. Like a prostate exam right? Haha.