Symptom table
Incorrect pressure in the power steering
CAUTION: Do not hold steering wheel in full position for more than 30 seconds in a minute to avoid overheating of fluid and damage to seals.
High system pressure is almost always caused by a faulty relief valve in the PAS pump.
Insufficient system pressure is usually caused by a low fluid level or a slipping PAS pump drive belt, or one of the following: PAS system leaks, PAS pump relief valve failure, steering worm valve assembly failure, steering piston leak, worn components PAS pump or crankcase.
State |
Possible reasons |
Action |
Insufficient gain |
* Fluid leaks |
* Check for leaks, add fluid to reservoir. |
* Wrong system pressure |
* Perform a pressure test. |
|
* Power steering pump drive belt |
* Check for dirt and/or adjust tension. |
Steering gear malfunction
State |
Possible reasons |
Action |
Increased «return» through the steering wheel |
* Faulty steering damper |
* Replace steering damper |
* Slack or play in the steering gear |
* Check steering gear and replace worn or defective parts. |
|
* Loose or worn bushings in the front suspension |
* Check suspension and replace worn or defective parts. - When replacing suspension bushings, replace ALL bushings and fasteners. |
|
* Incorrect hub resistance |
* Check kingpin bearing preload. |
Fluid leaks
CAUTION: Do not hold the steering wheel in the full position for more than 30 seconds in a minute, as this may cause the fluid to overheat and damage the seals.
State |
Possible reasons |
Action |
Leakage of working fluid from the crankcase of the steering mechanism |
* Increased pressure in the system |
* Replace the power steering pump. If the problem persists, repair the steering gear. |
Power steering fluid leaks |
* Incorrect fluid level. |
* Replenish or drain excess hydraulic fluid to bring the level back to normal. |
* Leakage from hoses and/or connections. |
* Loosen and tighten connections. Replace defective lines or hoses. |
|
* Outflow of working fluid through the filler cap. |
* Bleed air from the power steering system. |
|
* Worn or damaged steering component seal. |
* Replace defective seal (I). |
Insufficient gain - normal caster return action
State |
Possible reasons |
Action |
Insufficient Gain |
* Wrong tire pressure or wrong tire type |
* Adjust tire pressure and/or change tires. |
* Low fluid level or air pockets in the system |
* Bring the level of the working fluid to normal, remove air from the system. |
|
* Incorrect system pressure. |
* Check system pressure and bleed air from system. If the problem persists, replace the power steering pump and/or repair the steering gear. |
Heavy / hard steering operation - poor return effect of the angle of the longitudinal inclination of the axes of rotation of the wheels
State |
Possible reasons |
Action |
Hard or heavy steering work |
* Incorrect tire type or incorrect tire pressure. |
* Install correct tires or correct tire pressure. |
* Incorrect alignment or binding of the universal joint. |
* Loosen or replace the universal joint, align it correctly. |
|
* Improper steering adjustment. |
* Adjust steering gear. For more information refer to: Steering Gear Adjustment (211-00 Steering system - General information, General procedures). |
|
* Steering ball joints sticking. |
* Replace jamming elements. |
|
* Pivot pins require lubrication or bearing preload adjustment. |
* Lubricate kingpins or adjust bearing preload. |
|
* Worn or seized steering gear. |
* Repair the steering mechanism. |
Increased steering sensitivity. Increased play in the steering wheel
WARNING: Steering gear adjustments are not required during the warranty period. If the crankcase is under warranty, it must be returned to the manufacturer. Do not attempt to introduce side clearance.
State |
Possible reasons |
Action |
Light steering action / increased backlash |
* Incorrect steering adjustment |
* Adjust steering gear. For more information refer to: Steering Gear Adjustment (211-00 Steering system - General information, General procedures). |
* Worn Panhard bar bushings or trailing arms. Check the condition of the ball joints and the steering column lower shaft universal joint for wear. |
* Replace worn/damaged items. |
Steering vibration, angular oscillatory motion of the steered wheels
NOTE: Vibration transmitted through the steering gear is strong enough to cause high frequency steering wheel vibrations. Usually caused by wheel imbalance. However, there are a number of other possible causes for this symptom, which in a serious case can be described as an angular oscillatory movement of the steered wheels («shimmy»). Regardless of the terminology used by the owner/driver to describe symptoms, the following diagnostic checks should be performed in the sequence presented.
State |
Possible reasons |
Action |
Steering vibration |
* Wheel balancing, tire condition/brand. |
* Balance the wheels, replace faulty tires or tires of the wrong brand. |
* Faulty steering damper. |
* Replace steering damper. |
|
* Wear/reconciliation universal joints. |
* Replace worn parts, align hinges correctly. |
|
* Wear of the ball joints of the steering gear, including the steering mechanism and steering rod. |
* Replace worn or damaged items. |
|
* Deterioration of bushings of a suspension bracket. Incorrectly tightened fasteners. |
* Replace worn or damaged items. Tighten all fasteners to the prescribed torque with the vehicle supported on its own wheels. * If the problem persists, install the following steering damper kits: - Models 90 - STC288 (front end) and STC 289 (hindquarters) - Models 110/130 - STC290 (front end) - Models 110 (with alignment) - STC291 (hindquarters) - Models 110 (without alignment) - STC291 (hindquarters) - Models 130 - STC293 (hindquarters) |
|
* Improper power steering adjustment. |
* Adjust steering gear. For more information refer to: Steering Gear Adjustment (211-00 Steering system - General information, General procedures). |
|
* Increased axial clearance of the hub bearing. |
* Check the condition of the hub bearings and, if necessary, adjust the axial clearance. |
|
* Incorrect adjustment of the steering knuckle joints. |
* Adjust kingpin bearing preload. |
|
* Steering geometry not correct. |
* Perform a complete steering geometry test. |
Steering pull
State |
Possible reasons |
Action |
Steering pull - not when braking |
* Unevenly worn or defective front tires. |
* Inspect tires. Swap (from left to right) front tires. If the vehicle pulls in the opposite direction, change tires. If the problem persists, leave the tires in their new places. |
* Steering gear not centered. |
* Center the steering gear. For more information refer to: Steering gear centering (211-00 Steering system - General information, General procedures). |
|
Steering withdrawal - when braking |
* The presence of air in the brake system |
* Follow the bleed procedure. For more information refer to: Bleeding the brake system (206-00 Brake system - General information, General procedures). |
* Zagreasing brake pads |
* Eliminate clogging or replace brake pads. |
|
* Incorrect adjustment of the preload under the kingpin bearing |
* Adjust kingpin bearing preload. |
Course stability
State |
Possible reasons |
Action |
Sustainability |
* Vehicle overload or improper load distribution. |
* Check the vehicle boot parameters in the owner's manual. |
* Wear on rear trailing arms/chassis bushings. |
* Replace worn items. |
|
* Wear front and rear shock absorbers. |
* Replace worn items. |
|
* Faulty steering damper. |
* Replace steering damper. |
|
* Wheels are not balanced. |
* Balance the wheels. |
Power steering system - increased noise
State |
Possible reasons |
Action |
elevated noise |
* Incorrect fluid level. |
* Replenish or drain excess hydraulic fluid to bring the level back to normal. |
* Contact of hoses with the car body. |
* Lay the hoses away from the vehicle body. |
|
* PAS drive belt tension |
* Correctly tighten the drive belt. |
|
* Air in the power steering system. |
* Bleed air from the power steering system. |
|
* Faulty steering gear and/or pump. |
* Replace defective items. |
Checking the power steering system
NOTE: Loss of power steering efficiency. Before installing new elements, check the pressure of the hydraulic pump. To facilitate troubleshooting, use the troubleshooting table.
Pos. | spare part no | Name |
A. | - | Steering gear |
B. | - | Power steering pump |
C. | - | Hose from steering gear to pump |
D. | - | Hose LRT-57-030 |
E. | - | Test adapter LRT-57-001 |
F. | - | Pressure gauge LRT-57-005 |
G. | - | Thread adapter LRT-57-004 |
H. | - | Thread adapter LRT-57-022 |
1. A pressure gauge and test adapter are used to test the power steering system. This manometer is capable of measuring pressure of 140 kgf/cm2. The maximum pressure in the power steering system is 77 kgf/cm2.
2. In the event of certain malfunctions of the hydraulic pump, it is possible to achieve a pressure of up to 105 kgf / cm2. It is important to understand that gauge pressure is the same pressure that is applied to the steering wheel. When checking, gradually rotate the steering wheel, reading the pressure gauge.
3. Monitor and maintain the maximum fluid level in the reservoir.
4. Examine elements and connections of the amplifier of a steering on existence of leaks. All leaks should be repaired before attempting to test the system.
5. Check the tension of the power steering pump drive belt and replace the belt if necessary.
6. Assemble test equipment and install on vehicle as shown in RR3959M.
7. Open the tap of the adapter.
8. Bleed the system, being careful not to overload the pressure gauge.
9. In the normal state of the system, the pressure should be equal to:
- 1. (A) The steering wheel held in the limit position when the engine is running at a speed of 1,000 rpm, 70 - 77 kgf / cm2.
- 2. (B) The steering wheel, held in the limit position when the engine is idling, 28 kgf / cm2.
- 3. Checks should be carried out with the steering wheel in both limit / positions.
CAUTION: Do not maintain this pressure for more than 30 seconds in a minute to avoid overheating the fluid and damaging the seals.
10. Release the steering wheel and let the engine idle. The pressure reading must be below 7 kgf/cm2.
11. If the pressure values differ from those prescribed, there is a malfunction.
12. To determine if there is a malfunction in the steering gear or pump. Close the tap on the adapter for a maximum of five seconds.
13. If the pressure gauge does not show the prescribed pressure, the pump is defective.
14. Install a new pump, bleed the system and recheck. If there is low pressure or a significant imbalance, the problem is in the steering worm valve assembly.
Steering damper
NOTE: The power steering system, in addition to reducing the effort required to maneuver the vehicle into parking spaces, also helps dampen any wheel vibrations transmitted back to the steering wheel. When driving off-road, the wheels are often affected by potholes and bumps, causing the steering wheel to turn left and right. This phenomenon is called «steering feedback». To eliminate «steering feedback», a hydraulic shock absorber is installed in the steering gear between the steering rod and the differential housing. The shock absorber, which provides the same tensile and compression resistance, is sealed for life.
1. Inspect shock for body damage or leaks.
2. Clamp one end of the shock absorber horizontally in a soft-jawed vise. Compress and stretch the shock absorber by hand. The resistance should be the same in both directions.
3. If you feel that the damper performance is out of specification, install a new steering damper.
Visual and control checks
WARNING: Before driving the vehicle onto a public road for a road test, be sure to perform the following basic visual checks to ensure that the vehicle is in legal condition.
1.
NOTE: This information applies to standard tires fitted as original equipment.
Check and adjust tire pressure.
2. Check the condition of the tires. Inspect tires for signs of uneven wear, damage, and abrasion.
3. Check the tread depth. Make sure the make and type of tires and their general condition are the same for each axle.
4. Check wheel rims for signs of damage and increased runout.
Road test procedure
General steering/handling problems can usually be classified into one of the following categories. MOSTLY THEY RELATE TO THE SERVICE LIFE, CONDITION AND USE OF THE VEHICLE.
WARNING: All road tests must be carried out by qualified drivers on roads where the traffic situation allows the tests to be carried out without violating traffic laws.
1. Perform visual and control checks.
2. Confirm the general nature of the complaint during the conversation with the client, simulating, where possible, the conditions for the manifestation of the problem. Perform the following road test procedure to fix the problem.
3. Evaluation of the load on the steering - driving at a speed of 16 km / h. Turn steering wheel 90°, check self-centering. Self-centering should be the same at each limit position, but the steering wheel need not return exactly to position «straight ahead» without driver assistance.
4. Evaluation of the work of the steering - driving at a speed of 64 km / h in a straight line (without convex profile) road, check for steering slip. The vehicle must follow a straight path WITHOUT a tendency to curve. If the vehicle experiences a curb pull, the vehicle may have «sensitivity to the convexity of the transverse profile of the road». A slight drift in the direction of the convexity of the cross profile of the road is considered acceptable.
5. Course stability assessment - driving at 112 km/h or the maximum legal speed on a straight, level road. Perform a normal lane change. The car must quickly straighten out on a new straight line.
6. Braking evaluation (with medium effort) - driving at a speed of 96 km/h on a straight, level road. Apply a steady, moderate amount of braking force, noting any tendency to slip. Run the brake test three times. If a slip is noted consistently, perform a brake test on a roller stand.
7. Braking evaluation (with full effort) - driving at a speed of 96 km/h on a straight, level road. Apply full braking force, noting any tendency to pull. Run the brake test three times. If a slip is noted consistently, perform a brake test on a roller stand.
8. If the symptom reported by the customer is stiff steering or steering problems, follow the procedure for tight steering. If not, move on to basic checks and adjustments.
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