Isuzu Trooper (2000 year). Manual - part 44

2A–6

POWER ASSISTED SYSTEM

Condition

Correction

Possible cause

Shimmy, Shake or Vibration

Tire or wheel out of balance.

Balance wheels or replace tire/or
wheel.

Loose wheel bearings.

Replace wheel bearing.

Worn steering linkage ball joints.

Replace ball joints.

Worn upper or lower ball joints.

Replace ball joints

Excessive wheel runout.

Repair or replace wheel and/or tire.

Blister or bump on tire.

Replace tire.

Excessive loaded radial runout of
tire/wheel assembly.

Replace tire or wheel.

Improper wheel alignment.

Check wheel alignment.

Loose or worn steering linkage.

Tighten or replace steering linkage.

Loose steering gear.

Tighten housing bolts.

Tires not adequately inflated.

Adjust tire pressure.

Loose, bent or broken front or rear
suspension parts.

Tighten or replace the appropriate
suspension parts.

Faulty shock absorber.

Replace shock absorber.

Hub bearing preload misadjustment.

Adjust preload.

Hard Steering

Bind in steering linkage ball studs,
upper or lower ball joint.

Replace ball joint.

Improper wheel alignment.

Check wheel alignment.

Steering gear misadjustment.

Check and adjust pinion torque.

Tire not adequately inflated.

Inflate tires to proper pressure.

Bind in steering column or shaft.

Repair or replace.

Improper power steering system
operation.

Repair or replace.

Refer to “Power steering system diag-

nosis”

Too Much Play In Steering

Wheel bearings worn.

Replace wheel bearings.

Loose steering gear or linkage.

Retighten or repair.

Steering gear misadjustment.

Inspect and adjust steering gear
preload.

Worn or loose steering shaft
universal joint.

Retighten or replace steering shaft.

Worn steering linkage ball joints.

Replace ball joints.

Worn upper or lower ball joints.

Replace ball joints.

Poor Steering Wheel Returnability

Bind in steering linkage ball joints.

Replace ball joints.

Bind in upper or lower ball joints.

Replace ball joints.

Bind in steering column and shaft.

Repair or replace.

Bind in steering gear.

Check and repair steering gear.

Improper wheel alignment.

Adjust wheel alignment.

Tires not adequately inflated.

Adjust tire pressure.

Loose steering wheel nut.

Retighten.

Worn wheel bearing.

Replace.

POWER ASSISTED SYSTEM

2A–7

Condition

Correction

Possible cause

Abnormal Noise

Worn, sticky or loose upper or lower
ball joint, steering linkage ball joints
or drive axle joints.

Replace.

Faulty shock absorbers.

Replace.

Worn upper or lower control arm
bushing.

Replace.

Loose stabilizer bar.

Retighten bolts or replace bushings.

Loose wheel nuts.

Tighten nuts. Check for elongated

wheel nut holes.

Replace wheel if required.

Loose suspension bolts or nuts.

Retighten suspension bolts or nuts.

Broken or otherwise damaged wheel
bearings.

Replace wheel bearing.

Broken suspension springs. 

Replace spring.

Loose steering gear. 

Retighten mounting bolt.

Faulty steering gear.

Check and adjust steering gear.

Wandering or Poor Steering Stability

Mismatched or unevenly worn tires.

Replace tire or inflate tires to proper
pressure.

Loose steering linkage ball joints.

Replace ball joints.

Faulty shock absorbers.

Replace shock absorber.

Loose stabilizer bar.

Tighten or replace stabilizer bar or
bushings.

Broken or sagging springs.

Replace spring (pairs).

Steering gear misadjustment.

Check or adjust steering gear.

Improper wheel alignment.

Adjust wheel alignment.

Erratic Steering When Braking

Worn wheel bearings.

Replace wheel bearings.

Broken or sagging springs.

Replace spring (pairs).

Leaking caliper.

Repair or replace caliper.

Warped discs.

Replace brake disc.

Badly worn brake pads.

Replace brake pads.

Tires are inflated unequally.

Inflate tires to proper pressure.

2A–8

POWER ASSISTED SYSTEM

Power Steering System

There is some noise in all power steering systems.  One
of the most common is a hissing sound when the steering
wheel is fully turned and the car is not moving.  This noise
will be most evident when the steering wheel is operated
while the brakes are applied.  There is no relationship be-

tween this noise and steering performance.  Do not re-
place the valve unless the “hissing” noise is extremely ob-
jectionable.  A replacement valve will also have a slight
noise, and is not always a cure for the condition.

Condition

Possible cause

Correction

Rattle or Chucking Noise

Pressure hose touching other parts
of vehicle.

Adjust hose position. Do not bend
tubing by hand.

Tie rod ends loose.

Tighten or replace tie rod end.

Loose steering gear mounting.

Tighten steering gear mounting.

Steering gear misadjustment.

Check and adjust steering gear
preload.

Poor Return of Steering Wheel to
Center

Improper front wheel alignment.

Adjust front wheel alignment.

Center

Wheel bearing worn.

Replace front wheel bearing.

Tie rod end binding.

Replace tie rod end.

Ball joint binding.

Replace ball joint.

Tight or frozen steering shaft
bearing.

Replace steering assembly.

Steering gear misadjustment.

Adjust the steering gear.

Sticky or plugged steering gear
valve.

Repair or replace steering gear
valve.

Entry of air in the power steering
system.

Bleed the system.

Momentary Increase In Effort When
Turning Wheel Fast To Right or Left

High internal leakage.

Repair steering gear.

Turning Wheel Fast To Right or Left

Power steering fluid level low.

Replenish fluid.

Steering Wheel Surges or Jerks
When Turning Especially During

Insufficient pump pressure.

Repair pump assembly.

When  Turning  Especially  During
Parking

Sticky steering gear valve.

Repair or replace steering gear.

Parking

Power steering fluid level low.

Replenish fluid.

Excessive Wheel Kick Back or Loose
Steering

Air in system.

Bleed hydraulic system.

Steering

Tie rod end loose.

Tighten tie rod end.

Wheel bearing worn.

Replace wheel bearing.

Hard Steering or Lack of Power
Assist

Sticky steering gear valve.

Repair or replace steering gear
valve.

Insufficient pump pressure.

Repair pump assembly.

Excessive internal pump leakage.

Repair pump assembly.

Excessive internal steering gear
leakage.

Repair steering gear.

Power steering fluid level low.

Replenish fluid.

Unstable Engine Idling or Stalling
When Turning

Pressure switch of the power
steering pump or its harness is faulty.

Repair or replace.

POWER ASSISTED SYSTEM

2A–9

Power Steering Pump

Foaming milky power steering fluid, low fluid level, and
possible low pressure can be caused by air in the fluid, or
loss of fluid due to internal pump leakage. Check for leak
and correct.  Bleed the system. Extremely cold tempera-
tures will cause air bubbles in the system if the fluid level

is low.  If the fluid level is correct and the pump still foams,
remove the pump from the vehicle and check the housing
for cracks.  If the housing is cracked, replace the pump
housing.

Condition

Possible cause

Correction

Low Pressure Due to Steering Pump

Relief valve sticking or inoperative.

Replace relief valve.

Side plate not flat against cam ring.

Replace side plate.

Extreme wear of cam ring.

Replace cam ring.

Scored side plate or rotor.

Replace side plate or rotor.

Vanes sticking in rotor slots.

Repair or replace vanes and rotor.

Cracked or broken side plate.

Replace side plate.

High internal leakage.

Repair internal leakage.

Low Pressure Due to Steering Gear

Scored housing bore.

Replace housing.

Growling Noise In Steering Pump

Excessive back pressure in hoses or
steering unit caused by restriction.

Repair steering unit or pump.

Scored side plate or rotor.

Replace side plate or rotor.

Worn cam ring.

Replace cam ring.

Groaning Noise In Steering Pump

Air in the fluid.

Bleed hydraulic system.

Low fluid level.

Replenish fluid.

Pump mounting loose.

Tighten mounting bolt.

Rattling Noise In Steering Pump

Vanes sticking in rotor slots.

Repair or replace vanes and rotor.

Vane improperly installed.

Repair rotor and vane.

Swishing Noise In Steering Pump

Damaged relief valve.

Replace relief valve.

Whining Noise In Steering Pump

Scored side plate and vanes.

Replace side plate and vanes.

Steering Column Lock System

Condition

Possible cause

Correction

Will Not Unlock

Damaged lock cylinder.

Replace lock cylinder.

Damaged park lock cable.

Replace park lock cable.

Will Not Lock

Lock spring broken or worn.

Replace lock cylinder.

Damaged lock cylinder.

Replace lock cylinder.

Ignition switch stuck.

Repair or replace ignition switch.

Park lock cable damaged.

Replace park lock cable.

Key Cannot be Removed in
“OFF LOCK”

Ignition switch is not set correctly.

Correct ignition switch.

“OFF-LOCK”

Damaged lock cylinder.

Replace lock cylinder.

Faulty shift lock mechanism.

Repair or replace the shift lock
mechanism.

Column

Condition

Possible cause

Correction

Noise in Column

Universal joint loose.

Tighten joint.

Shaft lock snap ring not seated.

Place snap ring in proper position.