I have a 91 honda accord lx. It has a high pitch whistling sound that seems to be coming from behind the intake manifold. I have changed the plenum gasket and many of the hoses, but I just can't seem to figure out where the sound is coming from. When accelerating the sound subsides, but comes right back. Any suggestions?
Tiny hole in the intake manifold perhaps, or something in the clutch/torque converter if its only doing it at idle.
It might have a hole in the intake. Check it. Does it get louder as you accelerate?
check your pcv valve if a hose is a little loose on that it whistles really bad
It happens to all 90-93 Accords. I have the same intake sound in my 90 Accord. It's not a problem. Matter fact I think it sounds pretty nice!