This summer I purchased and installed an Airaid F.I.P.K. Kit for my 1997 F150 XLT. Everything went fine until the weather turned cold. When it did I started hearing a medium pitched hum comming from the engine compartment. Upon investigating, I discovered it was comming from the new Airaid intake.

The whine is comming from the metal temperature sensor housing retaind from the OEM air intake. It only happens when the temperature is cold (less than 45 deg F), the RPMs are around 1,000, and I am at idle or decelerating. If my foot is on the accelerator at all, there is no hum. I have had the air filter off and the hum still occurs but I can't tell from what part of the retained temp. housing it is comming from.

Can anyone help me with this? As far as I can tell it is not effecting the performance but it's darn annoying when you're stopped at a traffic light and your truck sounds like a miniature tug boat with it's whistle stuck in the on position!

I have the 4.6L gasoline engine in the 1997 F150 XLT. I would appreciate anyone's help with this problem.

 

Welcome to the site....great place....
I have heard alot of people say their Airaid systems make a whistling noise.
It's possible your hoses may have shrunk from the cooler temps,have you tried retightening the clamps? This could
cause a slight leak,maybe. That's about the only thing I could think of that would cause it... somebody else may have more
info on this,never heard a peep out of my K&N system,,good luck,,,,,98

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98 F-150 4.6 Litre XLT2wd Ext. cab
Yokahama AVS/ST's
prarie tan/tan int.
K/N gen.II fipk
custom dual exh/gibson rectangle tips/rear exiting.
color matched snuglid
Superchip!!!
Westin nerfs blk .powdercoat
Clear front corners
Euro tails(Altezza style)
Cobra 75WXST cb w/weather alert
[b]Kenwood cd w/Radio Shack speakers,don't laugh it sounds pretty good]
Viper 500HF Security system
On the way/wheels,tires,air dam, etc..etc.......
doin the monochromatic boogie
on the front end.Billet grilles on order
www.my-f150.com Still want to lift it,YESSS!
FENDER GUITARS,ROCK!!!
http://www.bigsandy.net
officialtomwaits.com
reverendhortonheat.com

WOW,what a cool site!

 

Bill45, I have been having the same problem since the weather turned cold here in NC. The problem had occured once prior to installing the Airaid system, but has been constant for the past couple of weeks now. When I hear the "hum" it appears to be coming from the air filter and the vehicle rpm's jump to around 1700 rpms. The noise and the rpms return to normal after my truck heats up and temporarily stops by reving the gas... I have a '97 F-150 4.6 Liter... but the problem doesn't seem to be isolated with it, my friends Ford Contour is doing the same thing... I plan on taking it to Ford if I can find time with work, looking forward to finding an answere...

 

If I had only read this post before I took a trip this weekend! I started my truck and it made a noise like a fan motor gone bad,vibration type noise, but quite loud, weather was around 30 degrees, which is not common here in Florida and I had never had any problems with my airaid, didn't know what it was but when I revved the engine, it went away, no cel. I had to go to Maryland, and I did. Along the way I was thinking what could be causing the problem, and the only thing I could think of was the maf sensor was oiled fron the K&N filter as the day before i WAS RACING A BIT AND HAD IT UP TO AROUND 115 MPH. Got to Maryland and decided to clean the sensor with windex and a swab, but got too agressive and broke the wire on the sensor. Needless to say, but the cel came on and had to drive around with the truck revving unpredictably. Got home tonight and read your post. Tomorrow I'll have to take out the airaid and chip, reset the computer and take it to the dealer and ask why my truck doesn't run right. I'm hoping that they will replace the maf under warranty. I would still like to run the airaid, has anyone figured out how to run one in colder weather, or how to solve the noise problem?

 

Are you positive that the noise is from your Airaid?.....Because I had the same noise you described but with out having installed the Airaid. The sound is like blowing in a coke bottle, whistle, whine....Mine started when it got cold and around 2000rpm's, and I have the 4.6L also. I was able to fix mine under warranty. It was the inlet heater coil hose on the fire-wall making a harmonic vibration. Ford revised the hose, problem fixed. To verify if this is the problem, clamp off the inlet heater hose on fire wall.

Go back to last week posts and look up the one I posted about this (whistle coke bottle sound fix). I give detail and part # and the web site of tsb.

I hope this helps!

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Mine too. It is a K&N FIPK and I live in the tropics.

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My Ride: 1998 F150 4x4 Lariat Supercab Flareside 5.4L in Oxford White/gold, ORP, Tow Package, 3.55 Gears.

Modifications: K&N FIPK, Stepshield door sill protectors, Performance Accesories 3" body lift, Lift Lips, Gabriel Gas Ryder LT VST Shocks, Daystar front anti-sway bar polyurethane bushings and 35x12.5R16.5LT BFG All Terrain KO's on 16.5x9.75 American Eagle 589's.

Photos at: http://www.communicomgroup.com/jmtruck

 

I've been experiencing the same situation, and I have the WMS Velocity Tube installed! I'll have my truck in for it's 30K mile check next week, and will ask about the noise. If anyone has heard a solution, I'd love to hear it before the trip.


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Paul...
99 White F-150 XLT SC Sport, 4.6L, Auto, Captain Chairs, Class III Towing Package, 3.55 LS, Sliding Rear Window, 4X2, CD, Soft Factory Tonneau Cover, K&N Filter, WMS Velocity Tube, Line-X Spray on Bed Liner, Gibson Side Swept Cat Back System, Superchips Flip Chip, and the Original F150online Decal...

What more is there!

ptarnuzzer@ikon.com

 

Hey guys I'm hearing the same problem! '98 F-150 4.6L, 50th Anniversary 4x4, K&M Filter, High Performance Chip, Flow Master exhaust. I had the same problem last year about this time (+/- 32deg F), but it was still under warranty then. So I took it in for service, the service manager knew immediately what the problem was, an APO or APV or A... something or other valve. Sorry I can't remember, getting to old! All I know is what ever they replaced, it resolved my problem then. I'm trying to locate my old service ticket to see exactly what they did, of coarse I can't find THAT one. Telephoned the local dealer to get them to call up my vehicle history, they just have transferred to a new computer system and the girl who knows all will be in tomorrow. Anyway, I'm curious to see what is causing this noise.

 

I found a fix for my situation in the message board archives. At first I couldn't believe it would help, but I was out of options.

When I installed the Aidaid intake there was a 3/4 inch hose that ran from the intake tube to the idle control sensor (ICS). It's attached to the carburator. On the stock intake there was a small plastic box about 2x2x1 inch inline between the stock intake and the ICS. Because it was hard to install with the Airaid system, I left it off. Afterall it was just a plastic hollow box! How could it hurt to leave it off.

Well as I said I was out of options so I reinstalled it with the Airaid system and guess what? No more hum! And the idle seems to be smoother. Like I said I couldn't believe it worked. But I did notice it had a Ford stamp on it and a part number so I guess it's more important than I thought. Guess thats why I'm not a truck mechanic.

Hopes this helps someone.

 

I have a 2000 5.4L with a propane bi-fuel conversion from Technocarb. Just last week it started to hum. I thought it was the propane at first but it does it running on either fuel. It's comming from the air intake somewhere. It's intrmittent and never seems to do it when it's cold only after the outside temp gets above 60 or so. I thought installing an Airaid would help but after reading the message board I'll have the dealer look at it at the next service. Also have a friend with a 96 Explorer V6 who has the same problem but his only does it when the outside temp is 100 +.

 

Call K&N -800-858-333-, tell them that you have a FIPK on a 4.6L. The dealer replace my clutch at 19,000 miles on my 4th visit trying to fix the HUM " thanks ford ". There is a problem w/ the " black gaskets " in cold climates, they sent me replacements that are orange/red. Will install on Sat. Bill45's fix is also suggested by K&N .......

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I heard the "hum" for the first time Tuesday and again this morning. Both times were the first times the truck has been exposed to temperatures in the upper teens and low 20s. Only happens at idle with no throttle and sitting still. If I pop the truck into neutral the sound will stay for a short time (I can almost get the hood open to look) before it stops on its own. If I bump the throttle, it goes away and I may not hear it for a few stops.

Has anyone truly solved this mystery yet?

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2000 F-150 XLT Sport, Silver 4-door Supercab StyleSide
Short Bed (Only way to fit in the garage)
17" Sport Wheels with BFG tires, 3.55 R, 4.6l V8, Auto (First one in 20 years)
In-Dash Single CD Player, 60/40 Split bench dark graphite

Mods So Far
K&N Filter, Gatorback Spray-In Bedliner, Llumar ProShield Window Tint
WMS Velocity Tube, Black Westin Step Bars

Future Plans
Superchip, Upgraded Speakers/Stereo
FlowMaster Exhaust

 

Could the hum be from removing the intake silencer? Or do people who haven't removed the intake silencer also have this problem?
It is so weird that it only happens below 30 35 or so degrees.

If it is not the silencer then it sounds like it could be the idle air valve that sounds like it is fluttering in it's orifice.

 

I just called K & N and I think the guy thought that I had a FIPK or whatever rather than just a K & N Filter. Anyways, he is sending me some new adapters or something and told me to use the original resonator box rather than the 90 degree tube that came with the kit. I played dumb to see what he would send, we'll see what he sends me.

 

Has anyone figured out what is causing this? I finally got the hood popped and jiggled the Velocity Tube with NO change in sound. It is definitely coming from the front of the engine and only happens when at idle and stopped. Yesterday, I re-installed the original intake system but it has not yet gotten cold enough to test.

[This message has been edited by Y2kXLTSport (edited 01-09-2001).]