Whistling sound from engine area when car is

Guessing you are saying you checked vacuum lines, the next probable place is the exhaust.
Can you tell where it is coming from? If the front end of the engine then remove belts one at a time to disable accessories.
You need to locate it. Use a piece of fuel line of a hose of some type, you should be able to move it around and locate the source of the whistle.

Possible restriction in exhaust have convertor checked for blockage

Clean intake

it sounds to me like it is a blower motor not the engine.(heater fan)

Sounds like there is a leaking vacuum hose some where on the engine...Put your face next to the engine or the general point of sound and go from there. But be ware of moving parts like the belts and fan with loose clothing....bad things come from wearing loose clothing next to stuff like that...:0

Whistling can be caused by vacuum leaks. look for hoses and tubes to be cracked or broken. The tick may be the sound of the injectors working or valve noise. more info needed.

Make sure all your vacuum hoses are connected on the engine side. There is a vacuum ball mounted close to or on the fender wall. Make sure that the hose is connected to the vacuum ball. Question: Has the engine started to run rough lately? And do you hear a hissing sound or whistle from the dash area?

Take some WD40 and with engine running spray some around all vacume lines if a line is leaking the engine will rev up, than you will know where its at, just watch where you spray it, stay away from exhaust and electrical as much as possible, you don't need to spray a whole lot,A intake gasget might be leaking too try around there consentrating around #1 cyl., just be carefull don't need a fire.

bearing in the a-c ,sounds like it needs a new 1 .not a easy fix

Often a whistling sound, from the engine bay anyway, is the sign of a vacuum line that is leaking. Might want to check all the vacuum lines for cracks and such and make sure they are all connected.