Why car make a whistling noise
There are reasons for why car makes whistling noise.
On some cases car makes whistling noise while start up.On some cases it makes whistling noise while accelerating. On some cars it starts making noise after driven for some time.
Check for vacuum leaks.Wheel bearing.
Check window seals.If the seal is loose,cracked worn out then it will let air enter the vehicle which causes whistling noise at high speed.
When the alternator is overworking it can produce a whistling noise that can vary with engine speed.
Exhaust leak issue.A plugged exhaust - Muffler or Cat, most likely.
A fan or power steering belt slipping. Tip a bit of water on the belt while the engine's running and see if the noise stops.
Most of the cases causes of a whistling sound would be a vacuum leak, or sticking idle control system.
If the engine idles abnormally high when you first crank it up, then the malfunction is definitely in the idle system.
If the whistling gets louder or changes pitch with increase in RPM, then it is a belt. I t may even stop altogether, and start back when you come to a slowdown, too.
To deal with fan belt making noise issue its suggested to use a scotchbrite pad, and 'clean' the pulleys with it.
A worn out timing belt tensioner causing this.
