So, sometimes when I’m stopped in traffic, my Honda makes a funny noise. It sounds like it’s coming from under the hood - in front of me somewhere. Maybe a wheel? Anyway, it’s like a short whistle that finishes on a higher note. I’ve had mechanics check it out, but of course it doesn’t do it when they listen! It’s very random.
When it becomes constant it will be easy to find, EGR valve is my guess.
Tape recorder under the hood is your best friend.
Record the car while you drive, and if you hear the noice, save the tape, and play it for the mechanic.
sounds like a vacume leak noise of some kind. Vacume is high when the engine is in idle which is is when stopped in traffic. If it was a constant whistle we would suggest a loose or cracked vacume hose. but since it is intermittent the EGR valve is a good guess.
If it happens when you’re stopped you can safely eliminate the wheels as possible candidates.
Perhaps it’s the cooling fan coming on.