the best books to check this out....
Chiltons
Hayes,
elecrtronically you can purchase a week pass for Oreilly's auto parts website. This will allow you access dealer schematics and dealer technician manuals. If you wanna drive to the Buick dealer, assuming you still have one in your neighborhod, they will have a schematic on the computer in their parts department. A copy of the brake system will be free. The Chilton's or Haynes manuals available at your local parts store are about 15 bucks each. good luck. I hope I never have to ask another car question in my life.(cause that would mean I would have to work on the thing)
If you look under the dash by the brake petal there is a fuse box and a diagram is on the cover of it.
How to change brake lines on a 1991 Buick Lesabre?
Dot 3
Small pedal on the left of the brake pedal - activates the rear brake to hold vehicle
press back down on the pedal
Cut the wire
Should have an access panel inside trunk
carb cleaner or brake parts cleaner
5/16" allen
33 Ft lbs
You may have a vacuum leak at the brake booster. Have the brake booster inspected.
Book time for replacing brake booster 2.6 hrs