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Home >> Ford >> 2000 >> Excursion 7.3 F, 4WD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1542 (Steering System - General Information) >> Diagnostic Tests >> Steering System >> Pinpoint Tests >> Pinpoint Test A: Steering Has Lack of Assist or Inconsistent Assist
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Pinpoint Test A: Steering Has Lack of Assist or Inconsistent Assist

WARNING: This page is about a different car, the 2010 Lincoln Town Car. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Hard steering or lack of assist is experienced when the steering wheel effort exceeds specifications. Hard steering can remain constant through the full turn, occur near the end of a turn or differ right to left. It is important to know the difference between hard steering/lack of assist and poor returnability/sticky steering.

This pinpoint test is intended to diagnose the following:

PINPOINT TEST A: STEERING HAS LACK OF ASSIST OR INCONSISTENT ASSIST 

  1. A1 CHECK FOR POWER STEERING FLUID CONTAMINATION 
    • Check the power steering fluid for contamination.
    • Is the power steering fluid contaminated? 
    1. YES  : FLUSH the power steering system. REFER to Power Steering System Flushing . CHECK the system for normal operation. If assist concern still exists, go to  A2.
    2. NO  : Go to  A2.
  2. A2 CHECK THE STEERING ASSIST WITH THE ENGINE RPM RAISED 
      NOTE: Do not hold the steering wheel at the stops for an extended amount of time. Damage to the power steering pump may occur.
    • Set the engine at 2,100 RPM and turn the steering wheel fully to the left and right.
    • Is steering assist normal with the engine RPM raised? 
    1. YES  : INSTALL a new power steering pump. REFER to POWER STEERING article.
    2. NO  : Go to  A3.
  3. A3 CHECK FOR A CHANGE OF ASSIST ON LEFT AND RIGHT TURNS 
    • With the engine at idle, turn the steering wheel fully to the left and to the right.
    • Does the steering assist change when turning from right to left? 
    1. YES  : INSTALL a new steering gear. REFER to POWER STEERING article.
    2. NO  : Go to  A4.
  4. A4 CHECK THE STEERING LINES AND HOSES FOR RESTRICTIONS 
    • Inspect the steering lines and hoses for damage, kinks or restrictions.
    • Are the steering lines or hoses damaged, kinked or restricted? 
    1. YES  : INSTALL new lines or hoses as necessary.
    2. NO  : Go to  A5.
  5. A5 MONITOR THE ENGINE RPM CHANGES 
    NOTE: Do not hold the steering wheel at the stops for an extended amount of time. Damage to the power steering pump may occur.
    NOTE: Make sure that the vehicle is on a flat dry surface, all accessories are in the OFF position and that the steering system is at normal operating temperature.
    • Connect the diagnostic tool.
    • Start the engine.
    • With the engine at idle, raise the power steering fluid temperature to 74-80°C (165-176°F) by rotating the steering wheel fully to the left and right several times.
    • While monitoring the Engine Revolutions Per Minute (RPM) PID with the scan tool, turn the steering wheel quickly to the left stop position and then to the right stop position.
    • Note the engine RPM during the turns.
    • Does the engine RPM change (even temporarily) more than 30 RPM when turning the steering wheel? 
    1. YES  : INSTALL a new steering gear. REFER to POWER STEERING article.
    2. NO  : INSTALL a new power steering pump. REFER to POWER STEERING article.
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