Pinpoint Test A: Steering Has a Lack of Assist Or Inconsistent Assist

Steering System

Pinpoint Test A: Steering Has a Lack of Assist or Inconsistent Assist

NOTE: Hard steering or lack of assist is experienced when the steering wheel effort is higher than normal. Hard steering can remain constant through the full turn, occur near the end of a turn or differ right to left.

This pinpoint test is intended to diagnose the following:

- Power steering fluid contamination

- Steering gear

- Power steering pump

- Power steering hoses

PINPOINT TEST A : STEERING HAS A LACK OF ASSIST OR INCONSISTENT ASSIST - RWD (Rear Wheel Drive) VEHICLES

A1 CHECK FOR POWER STEERING FLUID CONTAMINATION

- Check the power steering fluid for contamination.

Is the power steering fluid free of any contamination?

Yes
GO to A2.
No
FLUSH the power steering system. REFER to Power Steering System Flushing . TEST the system for normal operation.

If the assist concern is still present, GO to A2.

A2 CHECK THE STEERING ASSIST WITH THE ENGINE SPEED RAISED

- NOTICE: 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 speed to 2,100 rpm and turn the steering wheel fully to the left and right.


Is steering assist fully restored to normal with the engine speed raised?

Yes
INSTALL a new power steering pump.
No
GO to A3.

A3 CHECK FOR A CHANGE IN ASSIST ON LEFT AND RIGHT TURNS

- With the engine running 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?

Yes
INSTALL a new power steering gear.
No
GO to A4.

A4 CHECK THE STEERING LINES AND HOSES FOR RESTRICTIONS

- Inspect the steering lines and hoses for damage, kinks or restrictions.

Are the steering lines and hoses free from any damage, kinks and/or restrictions?

Yes
GO to A5.
No
INSTALL new lines and/or hoses as necessary. TEST the system for normal operation.

A5 MONITOR THE ENGINE SPEED CHANGES
NOTICE: 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 scan tool.

- Start the engine.

- With the engine running 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 to the right several time.

- Enter the following diagnostic mode on the scan tool: DataLogger- PCM.

- Monitor the Engine Revolutions Per Minute (RPM) PID while turning 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 speed change (even temporarily) by more than 30 rpm when turning the steering wheel?

Yes
INSTALL a new power steering gear.
No
INSTALL a new power steering pump.