anyone know what this noise is . just started after I changed the plugs and 1 COP. 1997 f150 Scab 5.4L 167k

 

https://www.youtube.com/watch?v=vLeYTEqC47M&feature=youtube_gdata_player

heres a link to a clip I got with my phone

 

Probably one of the pulleys, maybe a WP.

If I had to guess, the AC.
_________

Let it cool, pull the serp belt, restart,

Noise still present? Regardless, shut the engine back off, - don't let it get too hot.

Try to isolate the noise to one of the pulleys first off, then go from there.



BTW- Doesn't sound like allot of noise from here. - Go over your work, make sure the coils are loose and plugs are tight.

 

Hard to tell without getting a stethoscope and listening to each pulley. But the noise sounds similar to what I heard when the bearing went out on one of my idler pulleys.

 

plugs are tight went back over with torque wrench. I did the gotts mod to it also will that make that noise? sounds like when you take the air cover outdid a throttle body that sucking in of air noise.

 

Did you loose your MAF O-ring before putting it back together ?

Perhaps the intake isn't sealed correctly, - check your line-ups and clamps.

 

Gonna have to check that in the morning I did clean MAF just sprayed it. The noise honestly sounds like it coming from the throttle body where the plastic cover is on top of the engine. Driving me crazy as it is my daily driver

 

If there is a vacuum leak I think you will have an idling problem not a weird noise. With a Screwdriver and Hose you already have an instant stethoscope. You can also use PVC and a small screwdriver that will fit.

If the Noise is coming from the TB the Hose that connects to the Plastic tube to the PCV Valve has swollen due Oil Vaporization by burning Ethanol fuel. PCV Hose can only handle fuel fumes & they are not Oil Resistant.

Permanent Solution will be adding an Air/Oil Separator and using a Stretchable DPFE Hose. The Black substance on the Intake Manifold are not Carbon it's oil.

 

The belt tensioner or idler pulley (almost certainly one of them). Mine sounded like that suddenly after a fuel stop. I did a write up on this forum.
Takes 2 minutes to loosen the idler, remove the belt and spin the pulleys.

 

Took the belt off and spun each pulley. Definitely not the pulleys.The noise is definitely coming from the throttle body. Took the cover off and started it up and when I put my hand on top of the throttle body I can feel it vibrating and hear it more pronounced. Its like a weird humming noise. Is there something around the throttle body that I need to change to fix this noise. I don't have an idling issue, zero performance issues either. Just after I did the Gotts Mod Intake and sprayed the MAF and let it dry thoroughly this sound started. Will check the vacuum lines again, do the lines have to tight in each fitting, as one of the vacuum lines I pull off on the passenger side pulls out easy.