I own a 2005 Mountaineer. Sometimes it makes an odd siren noise somewhere in the rear of the vehicle. It usually does it while we're moving, but one time it made the noise while the Mountaineer was in park (running) and I was outside the vehicle. The noise sounds like there is a cop right behind you and hits his siren for a second. The noise never lasts more than a second or so. The noise is louder inside the cabin than it was the one time I heard it from the outside. I have no idea what is making the noise. It's annoying because it makes my heart skip a beat every time I hear it and I think I'm getting pulled over. Anyone have any ideas before I take it to a dealer?

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I know this is an old post but I'm still trying to resolve this issue. This is a warm weather and probably A/C related as some have suggested. Well, it's getting warmer the noise is starting again. I'd like to replace the rear expansion valve but I have a couple questions since I'm not familiar with A/C systems. Can someone tell me where this valve is located and if it is a part I can swap myself (or is it a part of the charged A/C system and needs to be changed by a mechanic?). If it is a mechanic fix, is it likely that this would be covered under my extended warranty? Thanks for the continuing advice.

 

lol I have no idea what that might be. I own an 02 Mountaineer and never really heard of someone running over a cop car not knowing it Check under the truck to make sure!


on a serious side, I have no idea what it might be. Ever have a dealer check it out for u?

 

The dealer is my next step. The noise is very random and the odds of getting it to happen at the dealership are probably rare. I'm hoping that they will have had similar issues before and will know what it is. Thanks for the reply.

 

I understand. I hope it gets fixed what ever might be the problem.

Just curious though, how do you like the Mountaineer so far? got any pics to share?

 

Is it AWD?

 

Well you never know someone could be playing a trick on u! My grandpa and bought a brand new chevy car and every thime he made a right turn it would make this click....click...click noice and it was only just over 2 months old! He finally got so tired (almost when crazy)of it the he ripped off the plastic where the handle is on the driver side door and hanging there on a string was a bolt with a note on it saying "HAHA it about time you found me!!" I dont think he ever bought a chevy again

 

Yes, it is AWD. You have the option (via in dash display) to select automatic AWD or locked AWD.

For the most part, we are happy with the Mountaineer. There are a few quirks we aren't happy with. The siren noise (fixable I hope), lack of speed sensitive volume on the stereo, doors that don't unlock when you shut the engine off, and other little things here and there. I've heard that I might be able to change the door locks to unlock with engine shut-off but I have not looked into it yet. We like the extra room compared to the Grand Am we traded in. With our two boys in the third row seat (car seats), we can fit three adults in the middle seat with reasonable comfort. We normally have the boys in the middle seat with the third row seat down for gear. I like that I can put down the center portion of the middle seat. I can fit my 7ft fishing rods down the center of the car. Power is acceptable with the V6, though not spectacular. We get about 19mpg highway and 15.5mpg in town. Again, not too spectacular.

We actually went to the dealer looking for an Explorer and ended up buying the Mountaineer instead. We thought it looked nicer, liked the interior better, and it had AWD. It was priced the same as the Explorers with comprable mileage. My wife is the primary driver (I drive my F150) and I don't have to worry about her using 4wd in inclement weather.

It's easy to be picky, but we're pretty satisfied. Now if I can just get the siren noise taken care of, it would be that much better.

 

Since you just mentioned that you have 2 boys, are you sure that there is not a toy fire truck or ambulance somewhere in the back that has a siren sound that activates periodically. It might be motion activated and that is why it seems to only do it while you are moving.

 

My wife drives a 2004 Explorer Eddie Bauer V8 with the AWD option. I, too, have noticed a 'whine' at certain times that seems to stem from the rear end of the vehicle. I can't for the life of me put my finger on it but, it's far from a 'siren' whine.... very subtle in fact.

I have it on my list of things to 'check out' when we take it in for a piddly warranty issue or two this summer... still have to get that damn AC compressor gap thingamajig figured out... the AC clunks on engagement.

It's been a solid vehicle thus far but, like you, we have a couple of little qwerks.

RP

 

The rear expansion valve is probably making the noise. I've had them before to where they'd make a slide whistle type noise every now and then. Does it do it only with the rear A/C on?

 

I'm 100% positive the vehicle is making the noise. I haven't been able to isolate the noise since it is so random. It really does sound like a police siren and not a whine. Like Rockpick said, it's one of those things that can wait until you have a few reasons to take it in for warranty work. Thanks for the help.

 

I can confirm that it DOES make the noise with the rear AC off.

 

Maybe Quintin can tell you where it is, but all suv's have a vent toward the rear of the vehicle. I guess it helps with the exchange of fresh air inside the vehicle. If something is blocking that vent.......?

 

I dunno, still sounds like the expansion valve singing. All that I've seen have done it with the rear A/C on, but I suppose it could do it with the system off as well - refrigerant is still whooshing around in the lines regardless.

 

I know this is an old post but I'm still trying to resolve this issue. This is a warm weather and probably A/C related as some have suggested. Well, it's getting warmer the noise is starting again. I'd like to replace the rear expansion valve but I have a couple questions since I'm not familiar with A/C systems. Can someone tell me where this valve is located and if it is a part I can swap myself (or is it a part of the charged A/C system and needs to be changed by a mechanic?). If it is a mechanic fix, is it likely that this would be covered under my extended warranty? Thanks for the continuing advice.