god awful howling noise

[fordfan86]

i made my own conical filter adapter based off of what i saw in the tech library about two years ago. the truck runs fine but every now and again its makes this god awful howling noise coming from the filter when it is at idle or a lower rpm range. its really annoying and i usually just crank up the stereo so i can't hear it but i would like to fix it taking the filter off works pretty good for shutting her up so to speak but i would never run my truck without a filter on it. any help would be greatly appreciated.

 

[James86]

Which one in the tech library? The shower drain one seems pretty half-baked to me and probably doesnt flow smoothly with all the rough edges. If you're set on running a cone, either get an actual adapter for it (they're about $5 - whoopdee) or get a MAF housing out of a Contour like I did for a while so you can slide the intake hose on one end and the cone on the other end and have holes for a mount on the MAF itself:

Version A:

Version B:

I got my kicks out of it and went back to a factory box since the filters are cheaper and its easier to maintain plus it eliminates all the problems from the damn element oil getting on the MAF sensor and the radiator spitting water on the filter.

This is what it looks like today:

Between porting and polishing the MAF housing, removing that air horn thing at the fornt of the box, and sticking with a smoother flowing section into the TB, I still get that responsiveness I had with the cone more or less, but better filtration. It's all sealed properly and passed a smoke test when I had it in the shop (turned out to be finicky O2 sensors but thats a diff story...)

What does your set up look like now and have you really noticed any sort of a difference?

 

[fordfan86]

hmm i like the contour idea, but yeah it more or less looks like the pvc shower drain thingy. i made it out of a piece of 3 inch pvc and a piece of 1/4 inch plywood so i could have something to mount the pvc to.

 

[James86]

I got the idea for the Contour MAF housing when my wife and I were cleaning out MAFS and i saw what her 1996 Contour 4cyl MAF looked like. I'm sure other Duratec's use a similar MAF housing, but not all Fords obviously have the same MAF sensor design. I mostly switched back because it was easier to stumble upon a 3.0 Vulcan MAF for porting & polishing experiments and it did make a difference, however, when changing equipment, I suggest ALWAYS leaving it possible to switch back, hence why I have two 3.0 Vulcan MAF housings - one P&P and one original if i need/want to go back. Give the Contour MAF a try if you want, since its not like you'll be welding it on or anything and if I recall, it is actually a slightly larger diameter than my stock one, but I think it's about the same that your 4.0 already has. Make notes before you head to a junkyard so you know what youre getting (and getting yourself into). Good luck.