Strange "whoop" sound?
 

My wife has a 2003 mountaineer and she would always say that every once in a while she would hear a very fast and high pitched "whoop" noise. I though she was crazy but i was driving it the other day and I heard it. It is coming from inside the cad maybe in back seat. It is not the radio because it was off, any ideas?

One possibility:

OASIS SPECIAL SERVICE MESSAGE NUMBER: 17217
MESSAGE TITLE: 2002-2004 EXPLORER 4DR/MOUNTAINEER - A/C HOOT ON ACCELERATION - HIGH AMBIENT TEMPERATURE

APPLICABLE VEHICLES :
2002 - 2004 TRUCK : 00070 MOUNTAINEER 00134 EXPLORER 4DR

OASIS MESSAGE :
SOME 2002-2004 EXPLORER 4DR/MOUNTAINEER VEHICLES MAY EXHIBIT A BRIEF HOOTING
NOISE DURING LIGHT LOAD ACCELERATION AT LOW SPEEDS, FROM 1000-1300 RPM. TO
DUPLICATE, OUTSIDE TEMPERATURES TYPICALLY MUST BE 85 DEGREES FAHRENHEIT (29
CELSIUS) OR HIGHER WITH HIGH HUMIDITY. TO SERVICE, PERFORM NORMAL
DIAGNOSTICS. IF A SPECIFIC ROOT CAUSE IS NOT IDENTIFIED, BE AWARE THAT
ENGINEERING IS CURRENTLY INVESTIGATING VIA THE QUICKER SERVICE FIX (QSF)
PROCESS. A SERVICE PROCEDURE WILL BE PUBLISHED AS SOON AS IT BECOMES
AVAILABLE. PLEASE CONTINUE TO SUBMIT CONCERN REPORTS (EDSR) FOR ANY VEHICLE
WHICH EXHIBITS THIS CONDITION. MONITOR OASIS FOR UPDATES.

Steve

2006 Mountaineer Premier, V8 AWD.

I'm getting a whooping noise that sounds like it's coming from the right rear side. Noise is intermittent, and most closely resembles the start-up of a police car siren. Noise lasts about a second, although on rare occasion it will drag on for a little longer than that, and sometimes it sounds more like a groan.

It happens regardless of whether I'm driving, stopped at a light, or in park.

I can't forcibly replicate the noise or predict when it will happen. If there were some kind of a pneumatic load leveling system in the rear end, I'd suspect that since the noise could almost pass as air leaking out. It's definitely coming from the back end of the car.

It doesn't sound like the same pitch as the back-up sensors. I also considered possible venting from the gas cap, but the noise happens regardless of tank level, temp, humidity, altitude, etc. Only other thing back there is the subwoofer, but it makes the noise regardless of whether the stereo is on or off.

I've had it to two different dealers, and neither could find anything in the Ford database and couldn't get the noise to replicate itself. They want to think it's everything BUT what I've described. Wind noise (replaced weatherstripping on a FRONT door), even though I've told them that it's coming from the rear end and I don't have to be moving for it to make the noise, aftermarket stereo (but it was doing it before I installed the aftermarket stereo), and they keep referring to it as a "pop" when I keep telling them it's a "whoop." I even printed out posts from several other owners have the same problem and gave them to the service rep to show that I'm not the only one having this problem. Yet there's apparently nothing in the Ford database of anyone else having this problem.

http://www.carcomplaints.com/Ford/Ex...rear_end.shtml

#s 66 and 73 at http://www.carcomplaints.com/Ford/Ex...shifting.shtml

If you have had this same problem and got it fixed, please let me know what your dealer did to solve it. It's not a something I can voluntarily replicate or predict when it will occur, so troubleshooting is tough. I'm thinking of riding in the 3rd row whenever my wife and I are in the car together so that if it makes the noise, I can pinpoint where it's coming from. Otherwise, I'm at a loss, and my dealer is too (or he doesn't want to deal with it.)

Thanks.

Follow-up: Found the following posted by someone else at http://ford.justanswer.com/explorer/...d-explorer-xlt

Trying to see if the noise happens when rear AC is on. So far, only hearing it when it is off so this person may be on to something. Anybody else?<!-- / message -->

Whooping noise
 

I am experiencing a similar problem. I have a 2004 explorer, 4.6 v8, 4 dr 2wd. My wife has heard it many times, me only once. I have read there is a problem with the rear bearings in the form of a TSB. Does anyone have info on this? Is it serious enough to have to replace the bearings? Or can I continue to drive it as is. I have suspected the AC but my wife said she turned it off and the noise continued. HELP! This is driving me nuts.

I have been having this exact same hooting noise with my 2005 Eddie Bauer that has 45,000 miles. The noise lasts only a second and is coming from the rear of the vehicle. The noise does get louder with acceleration. I took it to the dealership twice but they were unable to reproduce the sound and because I am a women and they haven't heard the sound, they look at me like I am crazy. Any assistance would be greatly appreciated. Thanks!

I have the same thing going with my 2007 4.6 explorer. sounds like a cop siren. also it makes a noise like farting after the truck is stopped, like air escaping from the fuel tank maybe. other than that we love the truck.

Explorer whoops
 

my 2007 explorer does the same thing under the same apparent conditions. I just tell peolple its haunted but the service guys are scratching their heads

Has anybody ever figured this out? My 2003 Aviator just started doing this. Scares the heck out of me... think a police car is trying to get my attention!!

Mike

I have a ford Explorer 2007 that does exactly the same thing, the ""whoop"" sound is driving me crazy and the local dealers cannot locate the problem. has anyone come up with a final answer or solution for this yet?

Same Issue; anyone know the reason!

RE: strange "whoop" sound
 

This is hilarious! My wife's '04 Limited also has made this sound regularly, at random intervals. However it has not happened in so long now that I forgot about it. It was an unnerving sound at first when we first bought it preowned in late '04, as it did sound almost like a police siren. Our Exp now has over 150,000 miles on it and I've not heard the sound in a number of years. I have done enought research on it, albeit after the warranty ran out, to be fairly certain that it does stem from a rear A/C unit issue and never had it into the shop for this issue. Fear not, the rear A/C in our Exp still blows cold and as strong as ever. If you're not under warranty still and don't have the money tree growing in the back yard I wouldn't sweat it.

Whoop/siren sound
 

I just bought a 2005 Navigator with only 27k miles on it- I have the same problem with the whooping or siren sounds coming from the rear. After researching on line (a lot of ford vehicles with this problem), it's primarily pointing to the rear thermostatic expansion valve. The part itself can be found pretty cheap (under 20 or 30 dollars), but I don't know yet how labor extensive it is. I am going to talk to the dealer tonight who sold me the vehicle to see if he will replace that and I'll let you all know if that fixes the problem!

Ford Explorer Whoop / Siren Sound Solution
 

Hi all,
I have a 2005 Explorer. If your car has dual climate control and is making an intermittent "whooping" or "siren" sound in the back, you need to replace your HVAC Heater Assembly module. You can log on to Official Ford Parts Site | Buy Motorcraft & OEM Ford Parts Online | FordParts.com. Input your make, model and then HVAC, Valves....and you will see the drawing. The part is $250. Your Ford Dealership will charge $800 to replace it. If you are a mechanic or mechanically inclined, you can replace the part yourself. It's funny how the dealerships can not seem to figure out the problem. It's also interesting to note when I ordered the part, somebody else tried to buy it from the Ford dealership. It sounds like a lot of folks are having this problem. However, Ford doesn't want to admit that they have a faulty HVAC system. In any case, I've posted a video if you want to see the part and try doing this yourself.