Air pump whinning noise
I did notice that it only whinned when the car was ideling. As soon as I tapped the gas it would quite down. It seemed like when there was pressure in the line the electric AIR motor was laboring to push the air, but when you revved it the exhaust would sorta suck the air on its own and the AIR pump would not make noise. But who knows?
Anyhow, my recomendation is remove it and have the codes edited out!


