2005 S80 AWD weird whining noise coming from engine

Iceberg8389 · Post by **Iceberg8389** » Tue Sep 15, 2015 7:35 pm

Video 1:

Video 2:

Can anyone help me with what this noise could be? Leaning towards vacuum leak. Only goes away when in gear with engine under load. It does not go away when the dipstick is pulled or oil cap is removed so I am ruling out PCV.

Iceberg8389 · Post by **Iceberg8389** » Wed Sep 16, 2015 6:28 pm

To add, I noticed today when I turn A/C on, the noise almost goes away. Still there but much quieter and almost non existant.

Post by **Vovo_merz** » Thu Sep 17, 2015 7:15 am

there is an easy way to rule out few things such as ac compressor, alternator, power steering and tensioner by removing the serpentine belt and starting the car if the noise goes away at least you know where to start, my guess would be the alternator. if the noise is still there night be your starter.
Good luck and please update once this is solved or you need more help

Iceberg8389 · Post by **Iceberg8389** » Thu Sep 17, 2015 10:39 am

Ok so I actually noticed that my serp belt needs replacing anyway, so while I have the belt removed, you are saying to start the engine and see if the noise is gone? If it does go away in that instance, then I know it's something in the accessory system.

I do not think it's the starter because it only happens when the car is warm. On cold start the noise is absent, only becomes audible when engine starts to reach temp. Also, when u turn engine off the noise will persist for 1-2 seconds after motor is off.

Post by **chrism** » Tue Sep 22, 2015 11:09 am

It sure sounds like a big vacuum leak. Accelerating the car or turning on the A/C is apparently applying enough load that the vacuum drops off enough to stop, or nearly stop, the squealing.

You said you also have a CEL caused by a MAF sensor fault. Follow the vacuum line from the intake manifold to the MAF (clipped under the lip at the top of the radiator support structure) and see if the hose is cracked/loose/missing or if the MAF itself is cracked.

Post by **Vovo_merz** » Wed Sep 23, 2015 8:39 am

Iceberg8389 wrote:you are saying to start the engine and see if the noise is gone? If it does go away in that instance, then I know it's something in the accessory system.

correct start it with out the serpentine belt and see what happens like I said its an easy test to rule out few things