Prob Silly Questions

[cybermonkey600]

hey all ,recently got a 95 1.6 petrol carina e and after drivin it the last few weeks was wondering about a few things- first there is a high pitch wistle \whine noise commin from the engine bay its been like that for a long time before i bought it. a mechanic thought it was the altenator bareing but when i replaced it was not the prob the pullys ar fine and 2 toyota mechanics both looked at it and couldnt figure it out we think its coming from the air intake not too sure but if its the air intake is there anything that can be done the gasket seems fine .!i was told not to worry and just keep drivin it which i will but it buggs me to know what it as ,and secondly the central lockin is odd i can lock the passenger door and 2 back doors by lockin the passanger door but lockin the drivers door only locks itself,not a big issue but is there a simple fix? other than that its a great car :)thanks any help or adivic would be great