Whistling sound from engine

[dan765]

2004 Hyundai XG350 with the Sigma engine, 133,xxx miles.

There is a whistling sound coming from what it sounds like the right side of the engine. I can especially hear it when I'm accelerating as the pitch goes up as the engine speed increases (and goes down as engine speed decreases).

Any idea to what might be causing this?

Thanks.

 

[Hokiefyd]

It could be an accessory bearing, a tensioner bearing, or even a bad serpentine belt. If it doesn't use a serpentine belt, check the tension on all of the individual belts.

 

[qdeezie]

+1 - More than likely something bearing or belt related.

 

[Brybo86]

While running take a long screwdriver and put the tip on various places on the engine that you suspect may be giving off the noise, then put the handle end to your ear making sure to completely seal the tragus(little flap of skin) to the ear canal. this should allow you to locate the culprit

Rev the engine by hand at the throttle body

Goes without saying but....Make sure you don't put the screwdriver into any moving parts.

 

[Eddie]

I use a wooden dowel for listing to engine parts.

 

[Olas]

https://www.machinemart.co.uk/shop/product/details/cht171-mechanics-stethoscope

 

[dan765]

Any chance that it's a vacuum leak somewhere?

 

[Kawiguy454]

could be a vacuum leak from dry or cracked hose. does the sound stay perfectly pitched to eng rpm or does it change pitch or warble. ...does it sound mechanical or like air whistling?

 

[dan765]

It changes pitch in relation to engine speed. I cannot tell if it is mechanical or air.

 

[DriveHard]

my vote is vacuum leak, or leak associated with PCV. My PCV hose fell off the intake track, and if made a whistle loud enough to hear with the windows up while accelerating.