Recently purchased an 02' F-350 5.4, has 175k on it and sounds and runs excellent after doing plugs, and replacing one coil pack (some of the plugs were over .100k gap)anyway last few days some time after starting and or while driving it will make this strange groaning/buzzing noise, that comes and goes, sounds like it coming from the air filter ?
I say air filter because first time I heard it I opened the hood, and noise was from air filter housing, tapped the housing and noise stopped, but it comes and goes at will,, any thoughts ?? ,,,Mark

 

I'll pull the housing apart and look for an ill-fitting filter---could be a sound coming from intake air trying to draw from two different locations.

While apart make sure the MAF is installed, that the duct clapms leading out of the housing are still tight.

Never heard of this myself---first time for everything though.

BTW please let us know what you find---could be helpful down the road.

 

Recently my son noticed the air cleaner has the sticker on it with #'s and V-10 on the sticker, stock air cleaner housing, does a V-10 and a 5.4/4.6 have the same air cleaner part #s ?

The air filter seems to fit nice and snug.

 

My crash book from 2010 shows all gas motors from 2000>2004 were the same, Ford P/N YC3Z-9600-AE current as of 2010.

HTH

 

OK, found the culprit, I failed to mention in my first post that we had also changed the IAC valve (air by-pass valve on the receipt) because of low idle and stalling, the replacement valve was making the Groaning/Buzzing noise, sometimes it would go away, when it came back we tracked it down with a stethoscope , went back to Auto Zone with replacement, picked up my free IAC installed it and all has been good since.