hello
i am wondering why i hear a kind of "jet noise" after around 2,5-3000 rpm. it is like a turbo noise "i have no turbo".Not that it is a problem but am i the only one.
sounds like the engine needs more air at that rpm?
can that be a cause of a bad city millage?

f150 99 4,6l 4*4 4:10 gear ratio
35*12,5-16 tires k&n filter superchip
and more not important stuff

 

Do you have the K&N filter only or the FIPK? Does it sound like the fan whirling during fan clutch engagement? Is it hot or cold?

------------------
2000 F-150 XL,RC,LB,5.4,4R70W,3.55LS,
Class III tow/Payload #3/Convenience pkgs.,
4-wheel disc/ABS,Chestnut/Parchment 40/60,
Ford bedliner & gas/wheel/spare locks,
3" cold air box modification,Superchip,
Dynomax ultra-flow welded 3" cat-back.

 

well max i only have k&n filter.
it sounds like it is comming from the fan, fan clutch?
temperatur around 15 on the celcius somewhere around 50 on farenheit.

 

My fan has made a very noticeable whirling sound under certain conditions since new. I've seen several threads about this; This seems to be the norm and proper function. The fan clutch controls fan speed depending on temperature.

------------------
2000 F-150 XL,RC,LB,5.4,4R70W,3.55LS,
Class III tow/Payload #3/Convenience pkgs.,
4-wheel disc/ABS,Chestnut/Parchment 40/60,
Ford bedliner & gas/wheel/spare locks,
3" cold air box modification,Superchip,
Dynomax ultra-flow welded 3" cat-back.