Loud whining sound
MITSUBISHI COLT VI (Z3_A, Z2_A)

Hoping someone can help, I have a Mitsubishi Colt Semi automatic 1.3, 2011. Bought about a year ago and I haven’t had any problems in terms of been able to drive the car etc. 

But about the last 3 months I’m

Hearing a very loud whining noise coming from the car BUT only when the cars been left for a few hours or over night so basically when the engine isn’t warm yet I’m guessing, so it makes this horrendous sound when I’m first setting off I can hear it when I start the engine and then even worse when I begin driving in the low gears. 

Once I’ve been driving for a bit I’m higher gears the sound will go. But when I leave the car for a bit it over night it will be right back there waiting for me. 

I’ve had 3 mechanics look at it and they all couldn’t pin point where or why it’s making the sound, the last mechanic told me he’s basically ruled everything out that he thinks could be making the sound, took the belts off, all of them as far as I’m aware checked the bearings, and anything else. 

It’s passed it’s MOT and drives fine but the noise is pissing me off. 

Be great if someone could help 

I have a video of it if anyone wants to hear it. 

Thanks