GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Chevy P12 Chassis 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Brake System Slow Release

Step

Action

Value(s)

Yes

No

1

Was the Hydraulic Brake System Diagnostic Check performed?

--

Go to Step 2

Go to Brake System Diagnosis

2

Was the Park Brake System Diagnostic Check performed?

--

Go to Step 3

Go to Hydraulic Park Brake Diagnostic (Inoperative/Does Not Release)

3
  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 rpm increase without the vehicle moving?

--

Go to Step 4

Go to Step28

4

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

Is the park brake cable corroded, kinked, or interfering with other components?

--

Go to Step 5

Go to Step6

5

Realign or replace the park brake cable(s). Refer to Park Brake Cable Replacement in Park Brake.

Is the repair complete?

--

Go to Step 28

Go to Step6

6

Inspect the park brake mechanism inside the drum for free movement without binding. Refer to Parking Brake Shoe Replacement in Park Brake.

Does the park brake internal components function properly?

--

Go to Step 8

Go to Step 7

7

Clean the park brake internal components and check for proper movement.

If the park brake still does not move freely, replace the park brake components. Refer to Parking Brake Shoe Replacement in Park Brake.

Is the repair complete?

--

Go to Step 28

Go to Step 8

8

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 9

Go to Step 10

9

Replace the mounting bolt sleeves and bolts as necessary.

Is the repair complete?

--

Go to Step 28

Go to Step 10

10
  1. Remove the caliper piston. Refer to Brake Caliper Overhaul in Disc Brakes.
  2. Inspect the caliper bore and the piston for scoring, corrosion, plating damage or pitting.

Is there damage to the piston or caliper bore?

--

Go to Step 11

Go to Step 12

11

Replace the piston or the caliper as needed. Refer to Brake Caliper Overhaul or Brake Caliper Replacement in Disc Brakes.

Is the repair complete?

--

Go to Step 28

--

12
  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 or misaligned?

--

Go to Step 13

Go to Step 14

13
  1. Disassemble and realign or replace components as necessary.
  2. Replace the brake pedal. Refer to Brake Pedal Replacement .

Is the repair complete?

--

Go to Step 28

--

14

Check the brake pedal for interference with other components. Inspect the brake pedal area for the following:

    • loose or misaligned the trim panels
    • loose components, wiring harnesses or aftermarket devices

Are there any loose or interfering components?

--

Go to Step 15

Go to Step 16

15

Realign or reposition components as necessary.

Is the repair complete?

--

Go to Step 28

--

16
    • Check for collapsed, dented, or bent brake pipes.
    • Check the brake hoses for sharp kinks.

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

--

Go to Step 17

Go to Step 18

17

Reroute or replace the brake hoses or pipes as necessary.

Is the repair complete?

--

Go to Step 28

--

18
  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 forward reservoir show movement, or spouting?

--

Go to Step 19

Go to Step 20

19
  1. Install the master cylinder reservoir cover.
  2. Loosen the master cylinder mounting nuts 13 mm (½ in).
  3. Separate the master cylinder from the brake booster.
  4. Apply the brake pedal 3 cm (1 in).

Does the booster output rod move?

--

Go to Step 20

Go to Step 21

20

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

Is the repair complete?

--

Go to Step 28

--

21

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

Is the repair complete?

--

Go to Step 28

--

22
  1. Remove the master cylinder reservoir cover.
  2. Inspect the brake fluid for contamination.

Is the brake fluid contaminated?

--

Go to Step 23

Go to Step 24

23

Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing . Is the repair complete?

--

Go to Step 28

--

24

Check the master cylinder outlet ports for restricted passages. Refer to Hydraulic Brake System Bleeding .

Are the outlet ports restricted?

--

Go to Step 25

Go to Step 26

25
  1. Overhaul the master cylinder. Refer to Master Cylinder Overhaul .
  2. Flush the hydraulic brake system. Refer to Hydraulic Brake System Flushing .

Is the repair complete?

--

Go to Step 28

--

26
  1. Check the brake pipes and the brake hoses for restricted passages. Refer to Hydraulic Brake System Flushing
  2. Check for the following:
    3. • 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 apply?

--

Go to Step 28

System OK

27
  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 brake hose or the brake as necessary.

Is the repair complete?

--

Go to Step 28

--

28

Verify proper brake system operation.

Does the original condition still exist?

--

Go to Step 1

System OK