Hi there. Recently I disconnected the battery for 30 mins in order to do an idle relearn after taking out the throttle body for cleaning. Just yesterday i could hear a noise coming from under the hood that is hard to explain. However, the noise did go away when the a/c was turned off. I was just wondering if any of you think this noise could be the result of disconnecting the battery, and if so what you think it could be. the noise is not a rattle or clunk. It doesn't even sound mechanical to me, which is not to say its not mechanical. It sounds more like a hum or something. Also once the car has been running for a while the hum sound comes in rhythmic spurts and doesn't stop, but when first starting the car it sounds constant. Any ideas?
