My 92 Lesabre Limited w/o self-leveling rear struts makings this clearly audible high-pitch noise when braking. It sounds like the high-pitch noise an electric pump would make, and it only happens after a while of driving when I brake, and only from 15mph to zero. The harder I press on the brake pedal, the louder it gets. Once I come to a stop and ease off the pedal, it stops. When I have either turn signal on, the pitch fluctuates with the clicks from the relay. I did a search here but did not find anything. The fuel pump was replaced when I bought the car in 11/05. Any ideas what could cause this?

Have you ever had an ABS flashing code? This sounds like the ABS pump is operating for some reason. Pull the ABS pump fuse under the hood and take it for a drive to see if the noise is still there.

The ABS light has come on only for the usual test itself. I'll try your suggestion, though, as that's something I did not think of. (I thought perhaps the car did have ELC but the former owners where too cheap to get the appropriate shocks and had somehow disabled the system...)

You can check for a ELC compressor under the hood on the drivers side fenderwell. You can also check for a 20 amp fuse in slot 12 of the fuse panel, under the driver side dash to see if there is a fuse in that location.:screwy:

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