GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 2001 🢒 Aurora 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Brake System Slow Release

Step

Action

Yes

No

1

Did you perform the Brake System Diagnosis?

Go to Step 2

Go to Diagnostic System Check - Hydraulic Brakes

2

Check the park brake lever for proper operation by doing the following:

  1. Turn the ignition ON.
  2. Press the park brake pedal until it stops. Verify the Brake Warning Lamp is ON.
  3. Depress and release the park brake lever. Verify the Brake Warning Lamp is OFF.

Did the park brake warning lamp turn OFF and the pedal return to its original height?

Go to Step 4

Go to Step 3

3
  1. Check the park brake assembly for interference, binding or for broken components.
  2. Lubricate or replace the park brake assembly. Refer to Parking Brake Lever Pedal Assembly Replacement in Park Brake.

Did you complete the repair?

Go to Step 23

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4
  1. Start the engine.
  2. Shift the vehicle into DRIVE.
  3. Attempt to move the vehicle by slowly pressing the accelerator pedal.

Does the engine speed increase without the vehicle moving?

Go to Step 5

Go to Step 7

5

Inspect the park brake cables for corrosion, kinks, or interference with other components.

Are the park brake cables corroded, kinked, or interfering with other components?

Go to Step 6

Go to Step 7

6

Realign, adjust or replace the park brake cable(s) as necessary. Refer to the appropriate procedure in Park Brake:

Did you complete the repair?

Go to Step 23

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7

Inspect the disc brake caliper mounting bolts for corrosion. Refer to Brake Caliper Inspection in Disc Brakes.

Are the sleeves or mounting bolts corroded?

Go to Step 8

Go to Step 9

8

Replace the mounting bolt sleeves and bolts as necessary.

Did you complete the repair?

Go to Step 23

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9

Ensure the caliper pistons are moving freely within the caliper housing,

Do the pistons move freely?

Go to Step 10

Go to Step 11

10

Repair or replace the caliper as needed. Refer to the appropriate procedure in Disc Brakes:

Did you complete the repair?

Go to Step 23

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11
  1. Inspect the brake pedal assembly for bent or misaligned components.
  2. Inspect the brake pedal for interference (binding) between the pedal and the booster input rod.

Is the brake pedal binding?

Go to Step 12

Go to Step 13

12

Disassemble and realign or replace components as necessary. Refer to Brake Pedal Bracket Replacement .

Did you complete the repair?

Go to Step 23

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13
  1. Check for collapsed, damaged, or bent brake pipes. Refer to Diagnostic System Check - Hydraulic Brakes .
  2. Check the brake hoses for sharp kinks.

Are the brake hoses or the brake pipes collapsed, bent, or kinked?

Go to Step 14

Go to Step 15

14

Reroute or replace the brake hoses or pipes as necessary. Refer to the appropriate procedure:

    •  ISO Flares Replacement

Did you complete the repair?

Go to Step 23

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15
  1. Remove the master cylinder reservoir cover.
  2. Rapidly apply the brake pedal 3 cm (1 in), observing the brake fluid in the reservoir.

Does the fluid surface in the reservoir show movement, or spouting?

Go to Step 17

Go to Step 16

16
  1. Install the master cylinder reservoir cover.
  2. Separate the master cylinder from the vacuum brake booster.
  3. Apply the brake pedal 3 cm (1 in).

Does the booster output rod move?

Go to Step 19

Go to Step 18

17

Repair or replace the master cylinder. Refer to Master Cylinder Replacement or Master Cylinder Overhaul .

Did you complete the repair?

Go to Step 23

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18

Replace the vacuum brake booster. Refer to Power Vacuum Brake Booster Replacement .

Did you complete the repair?

Go to Step 23

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19

Inspect the brake fluid for contamination.

Is the brake fluid contaminated?

Go to Step 20

Go to Step 21

20

Replace all of the hydraulic brake system rubber components.

  1. Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .
  2. Replace all of the hydraulic brake system rubber components. Refer to the appropriate procedures:
    3. •  Brake Pressure Modulator Valve Replacement in Antilock Brake System
  3. Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .
  4. Bleed the brake system. Refer to Hydraulic Brake System Bleeding .

Did you complete the repair?

Go to Step 23

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21

Check the brake pipes and the brake hoses for restricted passages. Refer to Hydraulic Brake System Bleeding .

Check for the following:

    • Low fluid or no fluid output
    • Spurting of fluid while pressing the brake pedal
    • Particles suspended in the fluid

Do any of the above conditions exist?

Go to Step 22

Go to Diagnostic System Check - Hydraulic Brakes

22
  1. Determine the area of the restriction. This will involve the disassembly of individual brake lines and checking for low fluid output.
  2. Flush the individual brake line or the brake hose.
  3. If the restriction cannot be removed, replace the restricted brake hose or the brake pipe. Refer to the appropriate procedure:
  4. Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .

Did you complete the repair?

Go to Step 23

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23

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2