power steering FORD MUSTANG 2003 User Guide

PINPOINT TEST I: REAR SUSPENSION NOISE z
WARNING: The electrical power to the air
suspension system must be shut off prior to hoisting,
jacking or towing an air suspension vehicle. This can
be accomplished by turning off the air suspension
switch. Failure to do so can result in unexpected
inflation or deflation of the air springs, which can result
in shifting of the vehicle during these operations.
z Raise and support the vehicle.
z Check the steering system for wear or damage. Carry out a
steering linkage test. Refer Section 211 - 00 .
z Inspect the tire wear pattern. Refer to Tire Wear Patterns
chart in this section.
z Are the steering components worn or damaged? REPAIR the steering
system. INSTALL new
components as necessary.
TEST the system for normal
operation.
No
GO to
H3 .
H3 FRONT SHOCK ABSORBER/STRUT CHECK
z
Check the front shock absorbers/strut mounts for loose
bolts or nuts.
z Check the front shock absorbers/struts for wear or damage.
Carry out a "bounce test".
z Are the front shock absorbers/struts loose or
damaged? Yes
TIGHTEN to specifications if
loose. INSTALL new front
shock absorbers/struts if
damaged. TEST the system
for normal operation.
No
GO to
H4 .
H4 CHECK THE FRONT SPRINGS
z
Check the front spring and front spring mounts/brackets for
wear or damage.
z Are the front springs or spring mounts/brackets worn
or damaged? Yes
REPAIR or INSTALL new
components as necessary.
TEST the system for normal
operation.
No
GO to
H5 .
H5 CHECK THE CONTROL ARMS/RADIUS ARMS
z
Inspect the control arm bushings for wear or damage.
z Inspect for twisted or bent control/radius arm.
z Are the control/radius arms damaged or worn? Yes
REPAIR or INSTALL new
components as necessary.
TEST the system for normal
operation.
No
GO to
H6 .
H6 CHECK THE STABILIZER BAR/TRACK BAR
z
Check the stabilizer bar/track bar bushings and links for
damage or wear.
z Check the stabilizer bar/track bar for damage.
z Check for loose or damaged stabilizer bar isolators or
brackets.
z Are the stabilizer bar/track bar components loose, worn
or damaged? Yes
REPAIR or INSTALL new
components as necessary.
TEST the system for normal
operation.
No
Suspension system OK.
CONDUCT diagnosis on
other suspect systems.
Test Step Result / Action to Take Klj . 54 ba
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4. While the noise is occurring, either place an EngineEAR probe near the IAC valve and the inlet
tube, or create a 6.35 mm (0.25 in)- 12.7 mm (0.50 in) air gap between the inlet tube and the
clean air tube. If the IAC valve is making the noise, install a new IAC valve.
5. Test the vehicle for normal operation.
Steering Gear Grunt/Shudder Test
1. Start and run the vehicle to operating temperature.
2. Set engine idle speed to 1200 rpm.
3. CAUTION: Do not hold the steering wheel against the stops for more than three to
five seconds at a time. Damage to the power steering pump will occur.
Rotate the steering wheel to the RH stop, then turn the steering wheel 90° back from that
position. Turn the steering wheel slowly in a 15° to 30° arc.
4. Turn the steering wheel another 90°. Turn the steering wheel slowly in a 15° to 30° arc.
5. Repeat the test with power steering fluid at different temperatures.
6. If a light grunt is heard or a low (50- 200 Hz) shudder is present, this is a normal steering system
condition.
7. If a loud grunt is heard, or a strong shudder is felt, fill and purge the power steering system.
Checking Tooth Contact Pattern and Condition of the Ring and Pinion
There are two basic types of conditions that will produce ring and pinion noise. The first type is a howl
or chuckle produced by broken, cracked, chipped, scored or forcibly damaged gear teeth and is
usually quite audible over the entire speed range. The second type of ring and pinion noise pertains to
the mesh pattern of the gear pattern. This gear noise can be recognized as it produces a cycling pitch
or whine. Ring and pinion noise tends to peak in a narrow speed range or ranges, and will tend to
remain constant in pitch.
1. Raise and support the vehicle. For additional information, refer to Section 100 - 02 .
2. Drain the axle lubricant. Refer to Section 205 - 02A for Ford 7.5 rear axles or
Section 205 - 02B for
Ford 8.8 integral axles.
3. Remove the carrier assembly or the axle housing cover depending on the axle type. Refer to Section 205 - 02A for Ford 7.5 rear axles or
Section 205 - 02B for Ford 8.8 integral axles.
4. Inspect the gear set for scoring or damage. Klj . 64 ba
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8.
CAUTION: Correctly support the power rack and pinion steering gear to avoid
damaging the gear and hoses.
Position the power rack and steering gear out of the way. 1. Remove the nuts and bolts.
2. Position the steering gear so the front suspension lower arm front bolt can be removed.
9. Support the front suspension lower arm with a jack stand inboard of the spring seat.
10. NOTE: Note position of the front coil spring (5310) in the lower arm spring seat. It must be
installed in the same position.
Using the special tool, compress the spring until it is loose in the spring insulator (5415). 11. Remove the front suspension lower arm pivot nuts and bolts. Klj . 3 ba
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6. Move the jack stand under the front suspension lower arm ball joint and raise the suspension
until the shock absorber is compressed to the previously established alignment mark (curb
height).
7. Tighten the nuts.
8. Remove the jack stand.
9. Install the power rack and pinion steering gear. Klj . 6 ba
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For low or spongy brake pedal concerns:
zcheck and, if necessary, refill the brake master cylinder reservoir.
z bleed the brake system and retest the brake pedal feel.
z if the brake pedal is still low or feels spongy, check the brake pedal mounting for looseness and
correct installation. Check the power brake booster and the brake master cylinder for loose
mounting. Correct as necessary and retest the system for normal operation.
For a slow or incomplete brake pedal return concern:
zinspect for binding, damage, correct installation or interference at the brake pedal.
z check the power brake booster for binding, damage and correct installation.
Vibration When Brakes are Applied
For vibration concerns when brakes are applied, perform the following procedure.
Visually inspect: ztire condition and pressure.
z suspension bushings and ball joints.
Correct as necessary. 1. Verify and isolate the concern. Brake roughness can be felt in: zthe steering wheel.
z the seat.
z the brake pedal.
2. After verifying the concern, check for related concerns in the: zOn- Line Automotive Service Information System (OASIS).
z Technical Service Bulletins.
3. Check wheel bearing end- play and correct as necessary.
4. NOTE: Begin at the front of the vehicle unless the vibration has been isolated to the rear.
Remove the tire and wheel.
5. Remove the brake caliper.
6. Measure and record the brake disc thickness. Install a new brake disc if the thickness after machining will be at or below specification. The specification is molded into the brake disc. Do z
Power brake booster
z Brake pedal linkage
z Vacuum booster hose
z Tires
z Foreign material Klj . 3 ba
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Pinpoint Tests
PINPOINT TEST A: THE BRAKES PULL OR DRIFT booster hose as
necessary.
z Red Brake Warning
Indicator Inoperative z
Circuit.
z Bulb. z
REFER to Section 413 -
01 .
z Brake Noise zDisc brake
component. z
MACHINE or INSTALL a
new brake component as
necessary. REFER to
Section 206 - 03 or
Section 206 - 04 .
z Hydro-Boost, No
Power Assist z
Power steering
pump.
z Linkage.
z Power steering
fluid flow.
z Hydro-boost unit. z
Go To Pinpoint Test E .
z Hydro-Boost Erratic
Operation, Sticks,
Binds or Grabs z
Supply hose.
z Hydro-boost unit. z
Go To Pinpoint Test F .
z Hydro-Boost Brake
System Operation
Suspect z
Leakage.
z Hydro-boost unit. z
Go To Pinpoint Test G .
Test Step Result / Action to Take
A1 CHECK THE TIRES
NOTE:
Check tire pressure with the brakes off.
z Check tires for uneven and excessive wear and for correct
pressure.
z Are the tires OK? Yes
GO to
A2 .
No
CORRECT as necessary.
RETEST for normal
operation. A2 CHECK THE ALIGNMENT
z
Check the caster, camber and toe. Refer to Section 204 -
00 . Yes
GO to
A3 .
No
CORRECT alignment as
necessary. REFER to Section 204 - 00 . RETEST for correct
operation. Klj . 6 ba
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PINPOINT TEST D: EXCESSIVE/ERRATIC BRAKE PEDAL TRAVEL
PINPOINT TEST E: HYDRO-
BOOST, NO POWER ASSIST 4481 kPa (510-
650 psi)? INSTALL a new proportioning valve.
RETEST for normal operation.
Test Step Result / Action to Take
D1 CHECK FOR SPONGY PEDAL
z
Key in ON position.
z Operate the brake pedal and note pedal feel.
z Does the pedal feel spongy? Yes
BLEED the brake system. REFER to
Bleeding —
System in this section.
RETEST for normal operation.
No
GO to D2 .
D2 CHECK THE BRAKE PEDAL
z
Inspect the brake pedal and bracket for
binding, obstruction or damage.
z Is the brake pedal OK? Yes
GO to
D3 .
No
REPAIR or INSTALL a new brake pedal as
necessary. RETEST for normal operation. D3 CHECK THE BRAKE COMPONENTS
z
Inspect the calipers bolts, anchor plate bolts
and anti- rattle springs for binding, damage,
contamination and correct installation.
z Are the bolts and springs OK? Yes
GO to
D4 .
No
REPAIR or INSTALL new components as
necessary. RETEST for normal operation. D4 CHECK THE BOOSTER AND MASTER
CYLINDER z
Check the power brake booster and brake
master cylinder for correct installation and
correct push rod adjustment. Refer to
Section 206 - 06 and to Section 206 - 07 .
z Are the power brake booster and the
brake master cylinder OK? Yes
INSPECT the front wheel bearings for
wear, damage and correct installation and
the rear axle end play. CORRECT as
necessary. RETEST for normal operation.
No
CORRECT as necessary. RETEST for
normal operation.
Test Step Result / Action to Take
E1 CHECK FLUID LEVEL IN POWER STEERING
PUMP z
Check fluid level in power steering pump.
z Is level within specification? Yes
GO to
E2 .
No
CHECK for leakage of power steering
fluid. ADD fluid as necessary. E2 CHECK ACCESSORY DRIVE BELT Klj . 10 ba
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PINPOINT TEST F: HYDRO-
BOOST ERRATIC OPERATION, STICKS,
BINDS OR GRABS z
Check accessory drive belt tension and
condition. Refer to Section 303 - 05 .
z Is the accessory drive belt OK? Yes
GO to
E3 .
No
INSTALL a new accessory drive belt.
REFER to Section 303 - 05 .
E3 CHECK POWER STEERING HOSES
z
Check power steering pressure hoses, power
steering gear pressure hoses and power
steering return hose for cracks or leaks.
z Do power steering pressure hose, power
steering gear hose and power steering
return hose check OK? Yes
GO to
E4 .
No
INSTALL new hoses as necessary.
REFER to Section 211 - 00 .
E4 CHECK BRAKE PEDAL LINKAGE
z
Check brake pedal linkage for binding or
sticking operation.
z Does pedal linkage check OK? Yes
GO to
E5 .
No
INSTALL new pedal linkage as necessary.
REFER to Section 206 - 06 .
E5 CHECK POWER STEERING PUMP SPEED
z
Check engine idle speed against
specifications.
z Is engine idle speed OK? Yes
GO to
E6 .
No
SET engine idle speed to specification.
REFER to Powertrain Control/Emissions
Diagnosis (PC/ED) manual. E6 CHECK FOR PLUGGED RETURN HOSE
z
NOTE: The return hose from the oil cooler to
the power steering reservoir has an in- line
filter in the hose.
z Disconnect power steering return hose from
power steering fluid cooler and power
steering pump reservoir.
z Pass air through hose from the oil cooler end.
z Is hose plugged? Yes
INSTALL a new power steering return
hose.
No
GO to
E7 .
E7 CHECK POWER STEERING PUMP FLOW
AND RELIEF z
Test power steering pump for correct flow
and relief pressure. Refer to Section 211 - 00 .
z Is power steering pump operating
correctly? Yes
INSTALL a new power brake hydro-
boost
unit. REFER to Section 206 - 07 .
No
INSTALL a new power steering pump.
REFER to Section 211 - 02 .
Test Step Result / Action to
Take F1 CHECK SUPPLY HOSE
z
Check for obstructions in power steering return hose and Yes Klj . 11 ba
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PINPOINT TEST G: HYDRO-
BOOST BRAKE SYSTEM OPERATION
SUSPECT connections between the power steering pump reservoir and
between the power steering pump reservoir and the hydro-
boost
power brake booster.
z Are there any obstructions? REMOVE
obstructions or
INSTALL a new
hose.
No
GO to
F2 .
F2 CHECK BOOSTER OPERATION
z
Have an assistant check the fluid in the power steering pump
reservoir while rapidly applying the brake pedal approximately one
inch.
z Does the fluid show any movement or spouting? Yes
System OK.
No
INSTALL a new
hydro-boost
assembly. Test Step Result / Action to Take
G1 CHECK BASIC OPERATION
z
Key in OFF position.
z Press and release brake pedal several times to deplete all
hydraulic pressure from the hydro- boost power brake
booster.
z Press and hold brake pedal with light pressure.
z Key in START position.
z Does the brake pedal fall slightly and hold, and is less
pressure now required to hold brake pedal at the new
position? Yes
Hydro-
boost is OK.
No
GO to G2 .
G2 CHECK FOR HYDRAULIC BRAKE LEAK
z
With engine running, press and release brake pedal several
times.
z Hold brake pedal down with medium pressure, 34- 47 Nm
(25- 35 lb- ft).
z Does brake pedal move toward floor? Yes
GO to
G3 .
No
GO to G4 .
G3 CHECK FOR LEAKS —
BRAKE FLUID LINES z
Check for leaks at brake lines, including brake master
cylinder and brake hose.
z Do components check OK? Yes
COMPLETE master cylinder
By-
Pass Condition Test in
this section.
No
INSTALL new hoses and
lines as necessary. G4 CHECK HYDRO-
BOOST CONNECTIONS z
Clean the hydro- boost power brake booster, power steering
pressure hose, power steering gear pressure hose and
power steering return hose and connection.
z Start engine and run at idle.
z Check hose connections for leakage.
z Do hose connections check OK? Yes
GO to
G5 .
No
REPAIR or INSTALL new
hose and connections as
necessary. G5 CHECK FOR HYDRO-
BOOST LEAK Klj . 12 ba
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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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