Thread: Help to diagnose a humming sound

Due to my basic knowledge this is a long shot to diagnose without being here to hear it but worth a shot..

started the car yesterday afternoon and immediately noticed a new sound

an audible humming sound about the same decible as the car itself, almost sounds like it’s suppoed to be there but it’s definitely not.

Air con is off - not this.
noise somewhat skips a beat (changes/reacts momentarily) when moving the steering wheel
noise also skips a beat when moving from drive to reverse etc
(assuming these point to some sort of belt (?) as they both make the engine move slightly)
Held fan momentarily and noise continued
sound is much easier to hear from UNDER the front drivers side or drivers front wheel arch
can hear while at idle but not while driving as it gets drowned out
sound is not very loud on the left side of the car OR from the top inside the bonnet
Might be a faint burn smell with it, no faults or temp rising though

any thoughts or tips on what to check?

waiting to get into a mechanic shop but all full due to aus day tomorrow

115k km odo

Originally Posted by Lukeis

I managed to find a mechanic and he has diagnosed an alternator bearing has gone.

$790 incl new alternator and labor to fit.

updated incase anyone has the same issues.

For exactly the reason I replaced mine after 6yrs (from new). We camp quite a bit, in remote areas. Didn't want any issues.