I have a 2013 f150 Ecoboost 3.5L V6. On sudden and heavy acceleration as in passing a vehicle, I get a whirring type noise (as in a whirring revolution). I do not have it at any other time. Could this be a turbo issue? thanks

 

it is more than likely a leaking exhaust manifold.
i have done both of mine of the same truck.

 

Can you get a video of what you are hearing?

Exhaust manifold, unless they are really bad, generally "seal" themselves as they heat up and expand. I had two warped and both did this until the one got really bad after a few months of driving with it.

Have you drilled the weep hole? Might be boggin down due to moisture.
When were the plugs changed?
How long have you owned the truck or did you just buy it?

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