It looks like and is a 3/8 inch allen wrench for a 91 park ave ultra and is a 3/8 allen wrench!
A repair manual for the 1998 Buick Park Avenue would have a brakes repair diagram. A popular book is the Haynes Repair Manual.
disc
Power brakes use engine vacuum to get their power. If the engine is out of tune, the loss of vacuum will cause it to run rough. Try changing the spark plugs.
The Buick Park Avenue Started In 1991
look on firewall on passinger side
It can be many things. Can be the ABS wheel sensors or something more serious. Your normal brakes will still work but your Anti-Lock brakes may not function.
How do you uninstall a starter for a 1997 Buick Park Avenue
Could be that a vacuum hose has come loose or is letting air into the power brake booster
The Buick LuCerne
Depends on the engine the Park Avenue had in it.
Yes, with another 1997 Buick Park Avenue.
They stopped making the Buick Park Avenue in the year 2005