Hydraulic pump sound ('90 IMP)

[Brad Hogg <roadhogg@xxxxxxx>]

>From my experience and understanding of the braking system on these cars,
this is completely normal.  You are correct, they do not employ engine
vacuum for brake boost, rather, there is a pump and a pressure vessel that
is kept at sufficient pressure to give you the brake boost you need.  Be
thankful you hear that pump running, it is when you don't is when you need
to start to worry.

----- Original Message ----- 
From: "Tim Clevenger" <tjclevenger@xxxxxxxxx>
To: <mailing-list@xxxxxxxxxxxxxxxx>
Sent: Friday, June 04, 2004 10:38 AM
Subject: IML: Hydraulic pump sound ('90 IMP)


Hi all,

When I'm driving my '90, about every third time I step
on the brake, I get a sound like a hydraulic motor
running for a few seconds.  Is that some kind of brake
booster, or is my ABS pump running when it shouldn't?
I would expect that this car would have vacuum brakes
like most others, so it wouldn't need a motor running.


Thanks.

Tim