SOME SORT OF NOISE RATTLE? HAS DEVELOPED IN MY ...
1996 Oldsmobile 98
December, 5, 2012 AT 10:45 PM
Some sort of noise (rattle?) Has developed in my car. When I turn on the ignition WITHOUT starting the engine, I will hear this noise. It ranges in length from 3 seconds upwards of about a minute inconsistently. I first thought it might be the antenna motor, since I have a power antenna. However, the noise doesn't occur when the antenna motor is activated. I managed to pinpoint the noise to be behind the right rear tire. There's something behind it that to my novice eyes looks almost like a pump of sorts. It's kind of a double cylinder that's incased and has several wires going to and from it. I noticed that some of these wires lead to the lights at the rear of my car. The image attached is from the outer edge of the car looking up and in. The wires are connected on the other side. It looks like it might have some kind of motor or something in it, but I'm just not sure. Can anybody tell me what this is and whether or not my assumption is correct?
That appears to be the pump for an automatic load-leveling system. The arrow points to the link between the rear suspension member and the height sensor on the body. The wires you might see going toward the lights is just because the various circuits have wires in the same harnesses.
If that pump is making noise for different lengths of time as you mentioned, it would be because the back end needs to be pumped up different amounts depending on the size of a leak or the size difference of the weight in the car after you load or unload something.