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Rattling near muffler when electrics on

06-13-2004, 09:23 PM
Hi everyone, I am new to this forum. Hope you are all patient as I know very little about cars. Open a PC crate and I can tear one apart, but I just about know where to top up fluids under the hood of a car.

I am a big Buick fan since buying my first one, a 97 LeSabre, the beginning of last year.

The last couple of days there has been a rattling sound coming from the rear passenger side near the muffler. This happens occasionally when driving, but also happened just now with just the electrics turned on.

It is hard to describe the sound but if you can imagine drinking a milkshake out of a metal cup with a metal straw and it is just about empty and makes that gurgling sound... that's about what it would sound like.

May be related to this: I ran the gas tank about as low as I would dare to take it just before this started happening. The noise is definitely on the opposite corner to the gas tank input though.

A couple of weeks ago I was in a car-deer accident and the rear passenger side door took a dent. No damage further back though. I am also overdue for an oil change, should take it in on Tuesday when my fellow car pooler drives me in.

Any ideas? If this has been covered by an earlier thread, my apologies. I don't have too much time to browse the forum and I drive the car 100 miles a day to work and back. It is my bread and butter.

06-13-2004, 11:06 PM
I don't think this has been covered before, You know more than most people do! If I ask someoune where there muffler is, they point to the tailpipe.

06-14-2004, 01:52 AM
I know what a muffler is cos that's what fell off my F-150! ;oP

06-16-2004, 01:53 AM
I think you said something very significant here on this topic, are you saying that you have heard the noise with the engine off but just the switch turned to the "accessory" position on the ignition???

This is a very important piece of information because of course this would allow you rule out a ton of different noises and vibrations caused by the running engine! Then you get to focus only on things that use electric power to operate.

Now I am going to ask you one more question that will seem totally unrelated, but it is also important. When you look at the wheels on your LeSabre, do you have a solid center cap that completely covers the lug nuts for the wheel, or do you have a center cap that allows those nuts to show through, in other words it has five holes in the center cap that allow you to see the wheel nuts. Some of these LeSabres were produced with an optional "gran touring" package that was indicated by the type of aluminum wheel used on the car. Buick had a special wheel for LeSabre's that were produced with this option. Now you may wonder why this has ANYTHING at all to do with the noise you hear! This matters because in 1997 only LeSabres with the gran touring package were born with "air suspension" or "automatic load leveling". So these cars have a really noisy air pump that is located either in the engine compartment or under the wheel well on the passenger side I believe. this could have something to do with what you are hearing, if one of the air lines running to the rear struts is clogged, damaged, etc. or if the pump is acting flaky it may cause a sound like this.

There are tons of other things this could be but i'll let you ponder some of these thoughts for now :)

06-16-2004, 02:05 PM
Thanks for your thorough reply, yes I was glad to hear it with just the electrics on, as it basically keeps the hood shut...

I do wonder if there is some damage to the air lines as you suggested, considering I have a big dent in my rear passenger side door until it goes in next Monday for body work after that car-deer. I will suggest that to the body shop people and maybe they'll spot something as they do their work.

All I know about the suspension is that it is "Dynaride". It is a "Limited" LeSabre but the wheels don't seem to be anything special.

06-17-2004, 09:35 PM
Don't know if it ties in or not, but I will go on record as saying my '91 Park Avenue has this "Dynaride" thing and the load-leveling feature. Maybe that's two words for the same thing, but I hate it. I think mine must have an air leak, because it seems to me that it runs more than it ought to. It makes the most obnoxious rattling noise (my noise comes from the left front under the hood), and you don't even have to have the key in the ignition. I always know when the kids are in the back seat of the car out in the garage waiting to go somewhere--the growling gives it away.

One day I was under it changing the oil and that thing went off a couple feet from my ear, and I nearly soiled myself. Just last week I was checking tires, and I heard air leaking from somewhere around the right rear tire--I don't know if that's normal or not; I suppose if it's trying to level things out and it's shoving air off to that corner of the car and it's leaking, that might explain why it runs more than I wish it did. If that leak had been in the tire, it'd have been restin'-on-the-rim flat in two minutes.

I guess it seems like a lot of gadgetry to put on a car for what I think is not much in return. But I, like the countless Buick-buying bluehairs who have gone before me and in whose footsteps I follow, sure like a cushy ride. And cushy it is. I just doubt the load-leveling adds much.

06-17-2004, 11:12 PM
Ha, well sir, Im 19, the first LeSabre I got was a 92 which was given to me by my grandparents, when that one finally died at 242k miles this year I purposely went out and bought a 2000 LeSabre Limited. One of the #1 features on my list was the "gran touring" package with the air suspension. Now in 2000 I believe all LeSabre's were equipped with the air suspension, but if you drive one that isn't, you will definitely feel a difference in the handling performance. In 1991 the Park Avenue only had air suspension if it had the "Gran Touring" which included the stiffer air struts, a tighter rack and pinion, and a higher 3.05 final drive axle ratio to give you more take-off power. The dynaride is a generic term that buick coined for the new suspension they came up with in the early 90's, but it is sort of a sham. None of the lesabre's / park avenues came without dynaride, because that is all they made. If you find a level ground and park your car for a while there, and then leave it parked for a about 40 minutes or so. When you come back and start her up again, the air suspension should NOT activate, if it does than you are bleeding air somewhere. My old 1992's air ride gave out in its later years, turned out that one of the bags on the rear strut was just completely rotted and leaking.

06-18-2004, 12:13 AM
Look at your rear shocks, there is an air tube connected to them, perhaps the clip that secures it has fallen off.

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