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Home >> Acura >> 2005 >> MDX Base >> Repair and Diagnosis >> Steering >> Power Steering >> Power Steering System >> Symptom Troubleshooting Index
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Symptom Troubleshooting Index

Find the symptom in the chart below, and do the related procedures in the order listed until you find the cause.

TROUBLESHOOTING SYMPTOMS

Symptom Procedure(s) Also check for:
Hard steering Troubleshoot the system (see SYMPTOM TROUBLESHOOTING  ).
  • Modified suspension
  • Damaged suspension
  • Tire sizes, tire varieties, and air pressure
Assist (excessively light steering at high speed) Check the rack guide adjustment (see RACK GUIDE ADJUSTMENT  ). Front wheel alignment (see WHEEL ALIGNMENT )
Shock or vibration when the steering wheel is turned to full lock
  1. Check the rack guide adjustment (see RACK GUIDE ADJUSTMENT  ).
  2. Check the drive belt for slippage (see DRIVE BELT INSPECTION ).
  3. Check the power steering pump fluid pressure with T/N 07406-0010001 (see PUMP PRESSURE TEST WITH T/N 07406-0010001  ) or T/N 07406-001000A or T/N 07406-001A101 (see PUMP PRESSURE TEST WITH T/N 07406-001000A OR T/N 07406-001A101  ).
  4. Replace the steering gearbox (see STEERING GEARBOX REMOVAL  ).
 
Steering wheel will not return smoothly
  1. Check cylinder lines A and B for deformation.
  2. Check wheel alignment (see WHEEL ALIGNMENT ).
  3. Overhaul the steering gearbox (see STEERING GEARBOX OVERHAUL  ).
  4. Check the ball joints for binding.
 
Uneven or rough steering
  1. Check the rack guide adjustment (see RACK GUIDE ADJUSTMENT  ).
  2. Check the drive belt (see DRIVE BELT INSPECTION ).
  3. Check for low or erratic engine idle speed (see IDLE SPEED INSPECTION ).
  4. Check for air in the power steering system due to low fluid level or an air leak at the pump inlet hose.
  5. Check for low fluid level in the power steering reservoir due to possible leaks in system.
  6. Overhaul the steering gearbox (see STEERING GEARBOX REMOVAL  ).
 
Steering wheel kicks back during wide turns
  1. Check the drive belt (see DRIVE BELT INSPECTION ).
  2. Check the power steering pump fluid pressure with T/N 07406-0010001 (see PUMP PRESSURE TEST WITH T/N 07406-0010001  ) or T/N 07406-001000A or T/N 07406-001A101 (see PUMP PRESSURE TEST WITH T/N 07406-001000A OR T/N 07406-001A101  ).
 
Humming noise from the power steering system
  1. Check when the noise occurs:
    • If the noise is heard 2-3 minutes after starting the engine in cold weather, this is normal.
    • If the noise is heard when the wheel is turned with the vehicle stopped, this is normal due to the fluid pulsation.
  2. Check for the high-pressure hose touching the subframe or body.
  3. Check for automatic transmission converter noise.
  4. Check for air bubbles in the power steering fluid or an air leak on inlet side pump.
  5. Check for particle contamination of the fluid and/or restricted filter in the reservoir.
Pump pressure
Power steering rack rattle or chattering
  1. Check for loose steering components (tie-rod and ball joints). Tighten or replace as necessary.
  2. Check the steering column shaft for wobbling. If the steering column shaft wobbles, replace the steering column assembly (see STEERING COLUMN REMOVAL AND INSTALLATION  ).
  3. Check the rack guide adjustment (see RACK GUIDE ADJUSTMENT  ).
  4. Check the power steering pump pulley:
    • If the pulley is loose, tighten it (see step  33 ).
    • If the pump shaft is loose, replace the pump (see PUMP REPLACEMENT  ).
 
Hissing noise/foaming fluid in reservoir
  • Check the fluid level. If low, fill the reservoir to the proper level and check for leaks.
  • Check the reservoir for leaks.
  • Check for crushed inlet hose or loose hose clamp allowing air into the suction side of the system.
  • Check the power steering pump shaft oil seal for leaks.
Air in the P/S fluid
Noise from the power steering pump
  • Compare the pump noise at normal operating temperature to another similar vehicle, (pump noise up to 2-3 minutes after starting the engine in cold weather is normal).
  • Remove and inspect the pump for wear and damage (see PUMP REPLACEMENT  ).
  • P/S pump pressure
  • Air in the P/S fluid
Squeaking from the power steering pump Check the drive belt (see DRIVE BELT INSPECTION ).  
Fluid leaks from the steering gearbox
  • Fluid leaks from the top of the valve body unit: Overhaul the valve body unit.
  • Fluid leaks from the driver's side boot. Replace the valve oil seal on the pinion shaft. Replace the cylinder end seal on the gearbox side.
  • Fluid leaks from the passenger's side boot. Replace the cylinder end seal on the cylinder side.
  • Fluid leaks from pinion shaft near the lower steering joint bolt: Overhaul the valve body unit.
  • Fluid leaks from the steering clamping valve covers on the valve body unit. Replace the valve housing.
 
Fluid leaks from the power steering line
  • Fluid leaks from the cylinder line A or B connections (flare nuts): Tighten the connection and retest.
  • Fluid leaks from damaged cylinder line A or B: Replace the cylinder line.
  • Fluid leaks from the pump outlet hose or return line fitting on the valve body unit (flare nuts): Tighten the fitting and retest. If it still leaks, replace the hose, the line, or valve body unit as necessary.
 
Fluid leaks from the power steering pump
  • Fluid leaks from the front oil seal: Replace the front oil seal.
  • Fluid leaks from the power steering pump housing: Replace the leaking O-rings or seals (see PUMP OVERHAUL  ) and if necessary replace the power steering pump (see PUMP REPLACEMENT  ).
 
Fluid leaks from the power steering reservoir
  • Fluid leaks from around the reservoir cap: Fluid level is too high; drain the reservoir to the proper level. Aerated fluid: Check for an air leak on the inlet side of pump.
  • Fluid leaks from reservoir: Check the reservoir for cracks and replace as necessary.
 
Fluid leaks from the power steering pump outlet hose (high-pressure)
  • Check the fitting for loose bolts. If the bolts are tight, replace the fitting O-ring.
  • Fluid leaks at the swagged joint: Replace the outlet hose.
 
Fluid leaks from the power steering pump inlet hose (low-pressure) Check the hose for damage, deterioration, or improper assembly. Replace or repair as necessary.