Engine makes a whistleing noise when in 5th gear :/ ??

[Ashley]

Just wondered if anyone new the reason as to why when I'm in 5th gear in my Chevrolet aveo 59 plate it makes a horrible whistling noise and I don't know why ?? it's only when I'm in 5th gear never any other :/ had it looked at by garages and they say it's fine but the sound irritates me

[AveoJoe]

sounds like it could be lots of things. 1. a vacuum leak 2. at higher speeds or 5th gear the plastic on wheel well or under the car could cause that sound. I would look under the car push in or tighten them plastic or black painted screws. good luck. Also check intake or filter.

[Ashley]

Ok mate thank you for that I will try to find the problem now I now what the possible problems are nice one