1995 Acura Integra Brakes died while driving

Hi spessegula,

Have you checked the brake fluids and brake pads wear?

If pumping action brings the pedal up, check the wheel bearings, they could be worn causing the clipers to be pushed back very far and this would cause the brake pedal to sink and the whirring noise.

Hi spessegula,

Sorry for the delay in replying.

Seems there is a problem and I am not getting any notification though you have replied.

When the brake pedal sinks, there are 2 possibilities :

1. Failing master cylinder or leaks in system. Do this test and let me know the results. With engine running, slowly depress the brake pedal with minimal force, does the pedal continue to sink? When resistance is felt, hold the pedal for a few seconds and if pressure fails when pedal starts to sink again, problem is a failing master cylinder.
Do you need to top up the fluid regularly? Any leaks would cause the pedal to sink?

2. Air trapped in system. When air is present in system, the first stroke of pedal would normally be much lower than normal and 2ns stroke would bring it up further. If this condition is present, bleed the brake system and retry.

The ABS would not cause such a problem unless the master cylinder fluid is leaking into the ABS pump which is quite common for vehicles of the year.

Does the ABS indicator light come on while driving?

After going through the above again, some of the things are getting clearer.

" About a week ago I started hearing a faint whirring (almost like a spinning or rotating) sound (while driving) coming from the left side of the front of the car. I did not notice anything unusual about the vehicle's condition and when I looked at the engine I did not notice anything out of the ordinary.
The sound continued most of the time that the vehicle was on. "

The noise should be intermittent and coming from the ABS pump motor. Under normal circumstances it should run briefly and stop. When it runs for too long, the ABS light would show. There could be a possibility the fluid level in ABS was low and has been topped up. However when the fluid level in ABS reservoir starts going down, there should be a leakage somewhere and it most probably is internal.

Since the ABS indicator is not showing, the item that is failing is the brake master cylinder.

Stop vehicle and depress the brake pedal lightly enough to prevent the vehicle from sliding. Hold for 10 seconds, if pedal sinks, the master cylinder is bad.

Yes, the ABS uses a separate reservoir and the brake circuit are parallel to the ABS system. However I have seen many instances of the ABS modulator leaking internally and when this happens, the fluid is leaking between the two system.

This would cause the ABS reservoir to reduce and brake master cylinder reservoir to increase or the other way round when the brake fluid level decreases and the ABS would overflow.

Yes, the symptoms do point to a failing ABS modulator and could be the cause of the low brake pedal.

If you see any small holes at side of modulator instead of rubber stopper, time to get the modulator replaced. Pressure is leaking internally and modulator being damp means fluid ios leaking from withing the stopper and forced the stopper out resulting in the hole.