Jim Grant's Tech Tips
Nissan Sentra, Soft Brake Pedal
Q: I own an 88 Nissan Sentra 2d hatchback
with 107,000 miles. I give the car a regular tune up and it runs great.
Just recently I noticed a problem with my brakes. Every time I apply the
brake pedal it is spongy at first then, with a pump or two, it stiffens.
What, if anything, can I do to correct the problem?
description indicates that the rear brakes may be out of adjustment or
there is air in the system. Check the brake fluid level. If its low,
top the reservoir off with fresh fluid. You need to know were that fluid
went! Have the brakes inspected and repaired as needed. As for brake adjustment,
the front disc brakes are self adjusting with each step of the brake pedal,
and work well. The same cannot be said for rear brakes, which are drum
type on your vehicle, and are suppose to be self adjusting. The problem
is the mechanism for the self adjusters are notorious for not self adjusting.
As the brakes wear, the distance from the braking material to the braking
surface increases. As the driver you will notice that the brake pedal
has to be pushed further to achieve braking. This is to make up for the
greater distance between the brake shoes and braking surface. When the
distance of travel becomes too great the brake pedal has to be pumped
quickly to move enough brake fluid to engage the brake shoes to the braking
surface. Inspection and proper brake adjustment should return the stopping
ability of your vehicle.