I recently got a 45,000 mile checkup from the Honda Dealer and everything turned out to be fine. They basically changed the oil and filter, lubed door locks and hinges, adjusted parking brake and other minor things. I also have a header, catback, CAI, plugs and wires on my car. For some reason I heard some very strange sounds emitting from my car today. It's only when I'm in D4 (Drive) and I am starting my car from a stopped position. It sounds like a grinding noise and I thought it was my brakes but I'm not sure. when I accelerate, however, the noise stops. The sound is also more prominent when I have the A/C on and the engine fans turn on. I called the Honda Service Center and the guy though my brake pedal assembly might need to be lubed but he wasn't sure.

I should also mention that I am using 87 octane gas now but I don't believe it's the pistons knocking cuz it would be louder and wouldn't stop, correct?

I noticed that when I had my SS header installed, I hear some weird sounds when not at WOT. It sounds like air is hissing or leaking from the header. I know it's not my CAI cuz I am very familiar with that sound. Do you guys think something could be wrong with my header- possibly a hole or not sealed correctly?

Thanks and if you need any more info, just ask.