Whats causing this noise? on 2003 Ford F-150 Lightning

My 2003 lightning has a high pitch whistling noise(sounds like a tea kettle) coming from behind the supercharger a little to the right. It only does it idling or when im at a steady speed but when I accelerate it stops. What could this be?

by in Beaumont, TX on February 08, 2012
2 answers 6 comments
ANSWER by on February 08, 2012
pcv elbow may have a vacuum leak causing this. common issue with these motors. Roy
COMMENT by on February 08, 2012
Thanks and if not replaced soon could it cause more of a problem?
COMMENT by on February 08, 2012
it will throw a code eventually. i would get it confirmed asap. Roy
COMMENT by on February 09, 2012
where exactly is the pcv valve. is there a website i can go to?
COMMENT by on February 09, 2012
It is on the passenger side valve cover. There should be a sticker with a diagram under the hood.
COMMENT by on February 10, 2012
It was the elbow thanks but when I took the hose off the intake I noticed just a little oil, was the elbow causing that or is it something else
COMMENT by on February 10, 2012
That is normal due to wear in the pcv valve just replace the valve
ANSWER by on February 08, 2012
It sounds like a boost or vacuum leak