Hello.

So my volvo S40 from 1996 begins to sound wierd when i turn the engine on. It last about 2-3 minutes then it fades out, like a fan or something turning around is slowly stopping.
It only happens when the car has been turned of for about 2 hours, if i start it after a quick shop etc the sound doesnt start.
I really hope for some help since my mechanic doesnt know what to do.

The car has AC

Link to clip with sound on youtube:
Thanks in advance for any inputs.

 

That is one scary sound.Open the hood and try to locate the general direction of the noise but noise so loud you should be able to pinpoint the exact location..

 

I know what that is.

 

ok - share migbro - I hear an old timey alarm, a dog wining and some kind of metal wheel or something spinning against something else that's metal

 

It's likely a timing belt path roller about to fail and toss the belt. How old is the timing belt and rollers? How many miles does the car have?

 

Hi. It have nothing to do with the timing belt. It only happens when the car is cold. ANd shuts of every time after 2 minutes. I found out that the sound comes from this little thing under the fusebox, anybody knows what it is?

 

That looks different than mine but it seems thats the electric vacuum pump for the brake?

 

Sounds like a noisy secondary air pump. Probably has water in it.