Hi folks. After completing several repairs recently, I'm stumped by this.

Today, I noticed a chattering/whirring sound coming from underneath the driver'* side rear of my '98 Olds LSS. When I looked, the sound was coming from this contraption:

Also, there were vacuum lines attached to it, all of which were dry-rotted. One had become detached. Another had holes in it. So I replaced them.

The chattering/whirring sound remained, though. It occurs at start-up. I checked after I drove it, and it had stopped. But it reoccurs at every start-up.

What is this? And should I be concerned about the sound it'* making?

Oops. Tried to post a pic. Trying again ...

Trying a link to the picture this time:

https://picasaweb.google.com/lh/phot...eat=directlink
Can you edit your posts in this forum?

Alrighty then..Do you have air suspension...If im not mistaken that would be the compressor for air struts..I may be wrong

I can edit your posts'* what ya need..Aactually going to merge them for ya

Actually, I'm not sure if I have air suspension or not. I'll have to check. I asked about the editing because I tried to post a pic. Didn't work.

Yeah i noticed..Like i said im not all that familiar with the oldsmobiles..somebody should be along shortly who will know more

Here'* the link to the picture:

https://picasaweb.google.com/lh/phot...eat=directlink

Okay, I might be getting a handle on this - a little. Still need someone to tell me if I'm right.

I think the picture shows the ELC compressor, and thanks to another thread (https://www.gmforum.com/showthread.p...+level+control), I understand it a little better. Right now, my very heavy tool box is sitting in the trunk on that side. So it sounds like the compressor is kicking in because of the added load. I just never noticed it before, and I don't know what a properly functioning ELC compressor sounds like.

I'm also wondering if it'* functioning correctly because I have no idea how long I've been driving with the rotted vacuum lines and what kind of effect it may have had. Guess I should check the other side, too.

Should the compressor kick in every time I start the engine as long as I have the extra load? In my case, it does. But it seems like once the height adjustment is made, it should stay put until the load changes. Yes? No?

BTW, the vehicle has 120k miles. Don't know if that'* a red flag for certain ELC components or not.

Any advice will be greatly appreciated.

Sounds like your on the right track..It may only be functoning upon start up due to lack of function when not running.

sounds normal to me mine pumps up usually a time or two as im warming it up depending on how many people i have in the car or stuff in the trunk. then will release some while were getting out and taking stuff out of the trunk.