My 2001 F-150 mass air flow sensor is making a trumpeting sound. I have
replaced the original with a new one. The sound is still there. No codes
show up when tested. I need help with this one.

 

Maybe is not the MAF. Have you checked that entire intake?

 

Thank you for your response. I have ruled out the MAF. I have traced it
to a hose that is connected to the intake. The hose goes to what appears to be some kind of diaphram located at the top of the intake.
I have been tryingto find a manual on the 4.6 so that I can identify
what the attachment does and if I can replace or rebuild it. If you
can help me with identifying this I would really appreciate it, or send
me to a website to see a view of the engine. I am very mechanically
inclined and was in my younger years a mechanic. I apologize for not
getting back to you sooner.

 

I have ruled out the MAF it is not the problem. I traced the noise to what appears to be a diaphram sitting on the intake. The hose from
it goes directly into the plastic intake wich connects to the oxygen sensor and the MAF to the intake. This truck was fitted with an after market intake filter. I would like to find a manual or picture to identify what
the unit is. Thanks for your help. Larry