This problem has been going on for a while.
after long drives a notice a significant power loss. When i park and rev the motor i hear a slight whistle almost like a vaccume.
It doesnt do it cold only after running it for a long time then get the whistle/vaccume sound.
Ive cleaner the egr ports,replaced egr valve, cat converter, plugs wires and alot of other new parts. Could the IACV need cleaned? Or im thinking fuel filter maby..... im completly lost im going crazy trying to figure this out its really annoying i could really use some help. Has anyone else has this type of problem. Also the idleing drops really low for a little when i put it into drive when ive been running it a long time. Thanks guy hopefully you guys can help. Thanks

 

Well, cleaning the IACV, adjusting the FITV and the fuel filter are "almost" maint items so I can't hurt anything.

Have you checked for stored codes?

Have you checked for vac leaks?

 

Warmed up=expanding head gasket=less compression=power loss=vacuum leak=whistling sound? Maybe? Never heard a head gasket make a whistling sound. Just grab a couple cans of intake cleaner. Spray all over your engine in pretty much every crease you can find especially around the intake with it running. If it bogs down or dies then you found the spot where its leaking.