brake booster vs. hydraullic accummulator

Henry A Harper III hah at
Mon Dec 13 15:49:25 EST 2004

> what is the diffrence between the 2? how do I know if one is failing
> versus the other...what are the symptoms? I assumed that my brake bomb
> went bad because i have no assited power...i can't stop in an
> emergency...if i slam on the brakes for an emergency there is a weird
> metal scrapping/taping noise...and the brake pedal vibrates hard....I
> was about to order a brake bomb when I noticed they had a listing for
> the brake now i am just confused

Metal whacking noise and vibrating brake pedal is what the antilock braking
system (ABS) produces when engaged, ideally along with non-locking of wheels
while stopping quickly. If you are getting ABS engagement resulting in
increased stopping distance, something is wrong like maybe a bad sensor or
rusty CV joint reluctor.

Bad bomb (hydraulic accumulator) usually produces symptoms of hard brake
pedal (when stomped at standstill or increased effort with fewer than 20
strokes after shutoff), most likely with red "BRAKE" warning light on
instrument panel if car is running. Bad servo (booster) should also result
in a "BRAKE" warning light but no whacking noises until you hit the cause of
your emergency stop situation.


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