2003 FORD MUSTANG vacuum

Component Tests
Brake Booster
1. Check the hydraulic brake system for leaks or insufficient fluid.
2. With the transmission (7003) in NEUTRAL, stop the engine (6007) and apply the parking brake control (2780). Apply the brake pedal several times to exhaust all vacuum in the system.
3. Apply the brake pedal and hold it in the applied position. Start the engine. If the vacuum system is operating, the brake pedal will tend to move downward under constant foot pressure. If no
motion is felt, the power brake booster system is not functioning. Continue with the following
steps.
4. Remove the vacuum booster hose from the check valve connection. Manifold vacuum must be available at the check valve end of the vacuum booster hose with the engine at idle speed and
the transmission in NEUTRAL. If the manifold vacuum is available to the power brake booster,
connect the vacuum booster hose to the power brake booster check valve and repeat Steps 2
and 3.
5. If no downward movement of the brake pedal is felt, install a new power brake booster.
6. Operate the engine a minimum of 10 seconds at fast idle. Stop the engine, and let the vehicle stand for 10 minutes. Then apply the brake pedal with approximately 89 N (20 lb) of force. The
brake pedal feel should be the same as that noted with the engine operating. If the brake pedal
feels hard (no power assist), install a new power brake booster check valve and retest. If the
brake pedal feels spongy, bleed the hydraulic system to remove air. For additional information,
refer to Bleeding — System in this section. Check Valve z
Engine running at idle speed.
z CAUTION: Do not hold the brake pedal at 444 Nm
(100 lb) force for more than 5 seconds at a time.
z Apply brake pedal with approximately 444 Nm (100 lb)
force and hold.
z Check hydro-boost unit input seal, housing seal,
accumulator seal, piston seal and spool plug seal for
leakage.
z Is hydro- boost unit free of leaks? Yes
GO to
G6 .
No
INSTALL a new hydro- boost
unit. G6 CHECK RESERVE RETENTION
z
Engine running at idle speed.
z CAUTION: Do not hold the brake pedal at 444 Nm
(100 lb) force for more than 5 seconds at a time.
z Charge system to pressure by holding the steering wheel at
stop or by pressing the brake pedal with approximately 444
Nm (100 lb) force.
z Key in OFF position.
z Wait five seconds.
z Press brake pedal and observe if there is any power brake
reserve.
z Is there any power brake reserve? Yes
Hydro-
boost unit is OK.
No
INSTALL a new hydro- boost
unit. Klj . 13 ba
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The function of the power brake booster check valve is to allow manifold vacuum to enter the power
brake booster and prevent the escape of vacuum in case manifold vacuum is lost during sustained full
throttle operation.
To test the function of the power brake booster check valve :
zStart and run the engine for at least 10 seconds.
z Operate the brake pedal to check for power assist.
z Disconnect the vacuum booster hose from the power brake booster check valve. Do not remove
the power brake booster check valve from the power brake booster.
z There should be enough vacuum retained in the brake booster for at least one more power-
assisted brake operation.
Brake Master Cylinder — Normal Conditions
The following conditions are considered normal and are not indications that the brake master cylinder
is in need of service.
Condition 1: During normal operation of the brake master cylinder, the fluid level in the brake master
cylinder reservoir will rise during brake application and fall during release. The net fluid level (i.e., after
brake application and release) will remain unchanged.
Condition 2: A trace of brake fluid will exist on the booster shell below the master cylinder mounting
flange. This results from the normal lubricating action of the master cylinder bore and seal.
Condition 3: Fluid level will decrease with pad wear.
Brake Master Cylinder — Abnormal Conditions
Changes in brake pedal feel or travel are indicators that something could be wrong in the brake
system. GO to Symptom Chart for abnormal condition diagnosis.
Bypass Condition Test 1. Disconnect the brake lines at the brake master cylinder.
2. Plug the outlet ports of the brake master cylinder.
3. Apply the brakes. If brake pedal height cannot be maintained, the brake master cylinder has an internal leak and must be rebuilt or replaced.
Compensator Port Check
The purpose of the compensator ports in the brake master cylinder is to supply any additional brake
fluid required by the system due to brake pad wear and to allow brake fluid returning from the brake
lines to the brake master cylinder to enter the brake master cylinder reservoir.
The returning brake fluid will cause a slight turbulence in the brake master cylinder reservoir. Klj . 14 ba
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DESCRIPTION AND OPERATION
Brake Booster —
Vacuum
Power Brake Booster
The vacuum type power brake booster (2005):
zis a dual diaphragm, vacuum assisted power brake booster
z reduces brake pedal force and travel distance.
z is located on the LH side of the bulkhead in the engine compartment, between the brake pedal
(2455) and the brake master cylinder (2140).
z is divided into separate chambers by the diaphragms.
z will not operate if vacuum is restricted or if any of the vacuum related power brake components
fail.
z is installed as an assembly.
If the power assist fails, the brake system will continue to operate with increased brake pedal effort.
Hose and Check Valve
The power brake booster check valve (2365): SECTION 206-
07: Power Brake Actuation 2003 Mustang Workshop Manual Item Part Number Description
1 2140 Master cylinder
2 2B560 Hydro-Boost
3 2005 Power brake booster Klj . 1 ba
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z
is located on the front of the power brake booster.
z is installed separately; (install a new grommet when installing a new check valve).
z is positioned between the power brake booster and the power brake booster hose.
z closes when the engine is turned off.
z in the closed position, traps engine vacuum in the power brake booster
z retains vacuum to provide several power assisted brake applications with the engine off. Item Part Number Description
1 2140 Master cylinder
2 2005 Power brake booster Klj . 2 ba
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REMOVAL AND INSTALLATION
Brake Booster —
Vacuum
Removal 1. Disconnect the battery ground cable (14301). For additional information, refer to Section 414 -
01 .
2. Remove the air cleaner housing. For additional information, refer to Section 303 - 12 .
3. Remove the brake master cylinder nuts.
4. Position the brake master cylinder (2140) aside.
5. With the engine off, depress the brake pedal (2455) several times to discharge the accumulator. Disconnect the booster vacuum hose.
6. Remove the stoplight switch self- locking pin.
SECTION 206-
07: Power Brake Actuation 2003 Mustang Workshop Manual Klj . 1 ba
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SPECIFICATIONS
SECTION 211-
00: Steering System — General Information 2003 Mustang Workshop Manual General Specifications
Item Specification
Lubricants
Motorcraft MERCON® Multi-Purpose (ATF) Transmission Fluid XT-
2- QDX MERCON®
Power Steering Gear
Turning effort 2.27 Kg (5.0 lb)
Turns lock-to-
lock 2.38
Power Steering Purge Vacuum
Vacuum 68-
85 kPa (20- 25 in/hg) Power Steering Pump —
CII Flow 9.8 liters/minute
(2.6 gpm)
Fluid @ 74°- 80° C (165°-175°
F)
Engine at 1,500 rpm Pressure 1,034 kPa
(150 psi)
Fluid @ 74°- 80° C (165°-175°
F)
Engine at 1,500 rpm Minimum capacity 3.4 liters/minute
(0.9 gpm)
Fluid @ 74°- 80° C (165°-175°
F)
Engine at idle
Pressure at 5,102 kPa (750
psi) Relief pressure 7,240-8,400 kPa
(1,050-1,230 psi) Power Steering Pump —
CIII Flow 9.8 liters/minute
(2.6 gpm)
Fluid @ 74°- 80° C (165°-175°
F)
Engine at 1,500 rpm Pressure 1,034 kPa
(150 psi)
Fluid @ 74°- 80° C (165°-175°
F)
Engine at 1,500 rpm Minimum capacity 4.7 liters/minute
(1.25 gpm)
Fluid @ 74°- 80° C (165°-175°
F)
Engine at idle
Pressure at 5,171 kPa (750 psi) Klj . 1 ba
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GENERAL PROCEDURES
Purging —CII Power Steering Pump
CAUTION: If the air is not purged from the power steering system correctly, premature
power steering pump failure can result. This condition can occur on pre- delivery vehicles with
evidence of aerated fluid or on vehicles that have had steering component repairs.
1. NOTE: A whine heard from the power steering pump may be caused by air in the system. The
power steering purge procedure must be performed prior to any component repair for which
power steering noise complaints are accompanied by evidence of aerated fluid.
Remove the reservoir cap. Check the fluid level. If necessary, fill the reservoir to the correct
level.
zUse Motorcraft MERCON® Multi-Purpose ATF XT -2-QDX or MERCON® equivalent.
2. Tightly insert the Vacuum Pump stopper into the reservoir.
3. Start the vehicle.
4. Using the special tool, apply maximum vacuum and maintain it for a minimum of three minutes with the engine speed set at idle. SECTION 211-
00: Steering System — General Information 2003 Mustang Workshop Manual Special Tool(s)
Vacuum Pump
416-
D002 (D95L-7559- A) or
Equivalent Klj . 1 ba
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5. Release the vacuum and remove the special tool.
6.
CAUTION: Do not overfill the reservoir.
Check the fluid level. If necessary, fill the reservoir to the proper level. zUse Motorcraft MERCON® Multi-Purpose ATF XT -2-QDX or MERCON® equivalent.
7. Reinstall the special tool. Apply and maintain maximum vacuum. Klj . 2 ba
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