Need Advice - Loud Noise at Fan Belt area

[Kim Law]

Hi All

I have a F10 523i (2011) mileage 96K. Detected loud noise driving at NSHW during Christmas break. Noise go off after switching off engine. Very loud noise coming from fan belt area but no faulty light comes up. Took it to local WS at Sin Ming, told to replace Fan belt and Fan Belt Tensioner (say may check Alternator as well). At that time, cant detect the noise only show them the recorded noise. Both items replaced last week but said Altenator look ok. Now this noise came back while driving yesterday, this time took it to the workshop with real evidence. They said could be Alternator jam cause the noise, I notice the noise is lower when accelerator is pressed. WS suggest replace Alternator. Other than that the car can drive and noise is on & off. seems to come up after long drive.

Any suggestion or advice?

 

[Frankie Ng]

Hi All

I have a F10 523i (2011) mileage 96K. Detected loud noise driving at NSHW during Christmas break. Noise go off after switching off engine. Very loud noise coming from fan belt area but no faulty light comes up. Took it to local WS at Sin Ming, told to replace Fan belt and Fan Belt Tensioner (say may check Alternator as well). At that time, cant detect the noise only show them the recorded noise. Both items replaced last week but said Altenator look ok. Now this noise came back while driving yesterday, this time took it to the workshop with real evidence. They said could be Alternator jam cause the noise, I notice the noise is lower when accelerator is pressed. WS suggest replace Alternator. Other than that the car can drive and noise is on & off. seems to come up after long drive.

Any suggestion or advice?

Did the workshop check the engine mounting kit?


Sent from my iPhone using Tapatalk

 

[Citizen69]

Something similar happened to my ride previously. Sounded like an aircraft whirring noise in underground carpark and yes, after the engine has heated up. For me it was the thermostat or something like that. It failed to detect the correct temp and thus turn the fan on at very high speed. Will wear the fan and belt out very fast. Changed it together with the belt and was fine after that. Hope it helps

 

[Kim Law]

Hi

Just went WS again, the noise is no more but when i happens it sounds like metal rubbing noise. WS claimed most likely Alternator inbuild gear is worn out, the metal spinning is rubbing against casing. No warning light from dashboard. Very loud and high pitch.

 

[Kim Law]

Hi all
Just want to close this thread that my issue was solved by PML. Outside can’t fix it as the noise was random and intermittent. PML replaced the whole engine cover that has exhaust valves that were clogged. Thus the high pitch noise when over heated.

The problem has been fixed for a year now.
Just for sharing.