Honda Pilot that EXL makes a hissing noise when push the pedal
 

I have a 2004 Honda Pilot EXL that makes a hissing/whining noise when push the pedal ,if the engine is hot. It seems to be coming from the passenger side of the engine bay. What's interesting is that the noise is more profuse when the engine is hot or, on long trips. Any suggestions? help ~
I have an extended power train warranty. will Honda cover the problem?