Noise-based diagnosis

When customers complain of abnormal noise or vibration coming from the steering system, diagnostics are performed based on that noise. Often this diagnosis must be made during a test-driving, driving under conditions similar to the owner’s usual driving. Since there is already a suspicion of a problem with driving, be sure to drive carefully and cautiously. Before testing on the road, thoroughly inspect the safety of vehicles, including tires. When a problem is identified during the test-driving, use the symptoms (pronounced noise) to identify a possible area of failure. Then check the parts in that area.

To determine the cause of the noise, redirect attention to where the noise is coming from. Some unusual sounds can cause tires or noise between the steering wheel and the steering column covers. Others may result from a faulty power steering pump or steering system. There can be many reasons for this, and some of them are outside the steering system.

The following are symptoms such as unusual noise that occurs during driving and possible causes of such noise:

Chirping or squeaking drive belt as the steering wheel moves from stop to stop:

• Loose or worn drive belt

Noise during cold start:

Blockage in the power steering fluid reservoir
Air in the hydraulic steering system

The steering grunts, growls, or shudders when turning or returning to the starting position at low speeds:

Air in the hydraulic steering system
Pinched hose of hydraulic system

Steering system clunk:

Air in the hydraulic system
U-joints
Steering gear

Steering gear squeak:

Improper servo oil in the system
Steering gear rotary seal
Steering column components

Power steering hissing or whistling:

Steering column shaft binding or misaligned
Damaged or worn steering gear input shaft and valve
Low oil pressure from the power steering pump
Restricted power steering lines

The power steering pump moans when the steering wheel is turned to the stop position:

Low oil level
Air in the hydraulic system
Steering oil reservoir blocked or damaged
Power steering pump bracket loose or damaged
Poor steering gear insulators

Power steering pump whine:

Air bubbles in the oil
Damaged power steering pump

Rattle, chuckle, knock or scrape is felt in the steering wheel when the vehicle is moving on a rough road:

Steering column shaft/coupling joints are worn or damaged
Loose, worn or damaged tie-rod ends
Loose or damaged steering gear insulators or mounting bolts
Loose mounting bolts on the steering column/transmission shaft
Worn or damaged steering column
Loose suspension bushings, bolts, or ball joints

Steering column rattle:

Loose bolts or mounting brackets
Loose, worn, or insufficiently lubricated column bearings
Worn or damaged steering shaft insulators
The steering column shaft/coupling is compressed or extended

Steering column squeak, grinds, or cracks:

Poorly lubricated steering shaft bushings
Loose or misaligned steering column covers
Touch steering wheel on steering column cover
Upper or lower bearing sleeves out of position