E36 325i jet engine whining sound, intermittent

[LCP]

E3six, no findings yet, weekdays means work work work work work... makan gaji life is always like that.

 

[LCP]

Vanos depends on throttle position and engine rpm. For the M50 single Vanos like mine, there are only 3 stages... at low revs it is at one setting (dunno whether retard or advance), somewhere in mid revs another setting, and another one at high revs. This is regardless of vehicle speed. The changing point is quite obvious on lower gears, you can actually feel the "kick" when accelerating hard.

When the sound came on, my throttle input is very light as I was just cruising, no acceleration or deceleration.... engine rev was kept stable at 3000rpm. And yet the sound came and went intermittently.

 

[tank34]

LCP, maybe we should clarify the "sounds" that we are hearing.

For the fan belt bearing issue, the sound is similar to that of an "old" electric shutter. You know, those shutters that are used as a front in retail stores at Shopping complexes. When the shutters are "old" and if you start the motor to either lift it up or down, you hear this metal screeching of metal against metal, possibly "worn" out bearings.

Same sound on my E46, except because it was runining at a higher speed, it ended up like a high pitch "screech".

 

[LCP]

The sound I heard is very much like a whine of an aircraft jet engine, it comes and goes. Only problem is it hasn't come back since.