Power steering pressure release valve

steering rack or gear . 2X2 - 4X4 engine . Depends on steering system .
When you turn the steering wheel, the steering gear rotates the pitman arm which forces the relay rod to one side. The tie rods connect to the relay rod with the ball studs. The tie rods transfer the steering force to the wheels. Use the tie rods in toe adjustments. The tie rods are adjustable. The pitman arm support the relay rod. The idler arm pivots on a support attached to the frame rail and the ball stud attaches to the relay rod.
The 2 tie rod are threaded into the tube and secured with jam nuts. Right and left hand threads are used in order to permit the adjustment of toe.

Binding linkage , steering gear worn etc....

Power Steering System Description and Operation (w/o Electro-Hydraulic Steering)
The hydraulic power steering pump is a constant displacement vane-type pump that provides hydraulic pressure and flow for the power steering gear. The hydraulic power steering pumps are either belt-driven or direct-drive, cam-driven.
The power steering fluid reservoir holds the power steering fluid and may be integral with the power steering pump or remotely located. The following locations are typical locations for the remote reservoir:
• Mounted to the front of the dash panel
• Mounted to the inner fender
• Mounted to a bracket on the engine
The 2 basic types of power steering gears are listed below:
• A recirculating ball system
• A rack and pinion system
In the recirculating ball system, a worm gear converts steering wheel movement to movement of a sector shaft. A pitman arm attached to the bottom of the sector shaft actually moves one tie rod and an intermediate rod move the other tie rod.
In the rack and pinion system, the rack and the pinion are the 2 components that convert steering wheel rotation to lateral movement. The steering shaft is attached to the pinion in the steering gear. The pinion rotates with the steering wheel. Gear teeth on the pinion mesh with the gear teeth on the rack. The rotating pinion moves the rack from side to side. The lateral action of the rack pushes and pulls the tie rods in order to change the direction of the vehicle's front wheels.
The power steering pressure hose connects the power steering pump union fitting to the power steering gear and allows pressurized power steering fluid to flow from the pump to the gear.
The power steering return hose returns fluid from the power steering gear back to the power steering fluid reservoir. The power steering return line may contain an integral fin-type or line-type power steering fluid cooler.
In a typical power steering system, a pump generates hydraulic pressure, causing fluid to flow, via the pressure hose, to the steering gear valve assembly. The steering gear valve assembly regulates the incoming fluid to the right and left chambers in order to assist in right and left turns.
Turning the steering wheel activates the valve assembly, which applies greater fluid pressure and flow to 1 side of the steering gear piston, and lower pressure and flow to the other side of the piston. The pressure assists the movement of the gear piston. Tie rods transfer this force to the front wheels, which turn the vehicle right or left.


Your best bet , take it to a qualified repair shop.

take it to a power steering specialist shop
the noise is from a pressure relief valve that unloads the pump pressure when it is not required for steering( idling, steering straight ahead or not steering wheel movement to activate the control valves)
the valve is faulty or the spring for the valve is failing and getting weak

Depends on what the noise sounds like. Some noise can be normal if you are holding the steering wheel at full lock . That is the pressure from the pump pushing hydraulic fluid through the steering box. If it is usually loud at the slightest turn..could be bad steering pump , leaking hose, leaking seal at steering box, even a bad belt.

If your reservoir is full then your power steering pump is most likely bad and needs replaced

driver error and nothing wrong with the power steering
the pump only produces pressure when the steering valves are up set and when the amount of turn is reached and the wheel is no further turned ., the pressure equalizes and then drops off until the valves are again upset
when the driver goes to full lock , left or right, and holds it tight against the lock stops, the pump keeps producing pressure until the pressure relief valve is activated
That is the whining sound as the valve vibrates
now the smoke is from the pump drive belt slipping from the extra load of the over pressurized pump
the leak is from the steering hoses starting to fail from the excessive pressure
good drivers with some intelligence goes to the lock stops then backs the wheel of just a bit to release the pressure on the pump
as I said driver error and it is all in the user manual

If the fluid is dark and thick, nothing is really going to make this system work optimally. You need to get the fluid replaced with new fluid before anything else. That, by itself might solve your problems.

Once you have done that, if you still have the problem, you have a bad spool valve. There is a valve that has a bobbin (or spool) that rides in a cylinder. When the spool is centered, the fluid pumped to the valve is returned to the reservoir. As you steer, if the wheels resist turning, that spool is shifted a little, closing the outlet to the reservoir a little, and an opening to the hydraulic assist is opened a little. The more you turn the steering wheel without the wheels re-aiming, the farther that spool moves, finally directing all of the output of the pump to the hydraulic assisting component.

If there is some foreign object that will not let the spool move that way, you won't get any assist that way. If the holes in the spool valve are blocked, the fluid will not get pumped to the hydraulic assist, and the pump pressure will rise quite high. There is a pressure relief valve, and new hoses can withstand this pressure, by older hoses will burst if subjected to this kind of thing. (This is why you should never hold the steering wheel at full lock on a power-assisted-steering vehicle.

It sound like what you need to do (this is what I would do) is remove the spool valve, drain all the fluid from the system, refill it, put in a new spool valve, and replace the fluid once more after about 20 minutes of running. Power steering fluid has a lot of detergent in it, so it can be used to clean the system...

This sound you speak of will not be transmission, nor RPM (Engine) related. It appears that your Power steering belt is either loose, or the PSP (Power Steering Pump Pressure Switch), may be bad. Is your Check Engine Light ever come on? When you say you're turning, the pressure supplied to the power steering system at low speeds is much greater than while driving down the Interstate. The only other "vibration or buzzing" noise would be coming from the rack and pinion assembly.

Have someone in the driver's seat with the parking brake on and engine started. With the vehicle on the ground, have them turn the steering wheel slowly through the full motions about three or four times. This purges the air (if there is any), from the power steering system. This also gives you the ability to "look" at the P/S Belt on right AND left turns to see as to whether your problem lays with air in the system or too much pressure.

By the way, NEVER use "Belt Dressing" on any of your belts. They sell the stuff, but it's just a quick fix to a belt sound. Use a round table candle to "lubricate your belts, for you probably already have a candle and it doesn't affect the belt or belt life.

Good Luck,

~Stillin~

"Still Living on the Right Side of Dirt..."

check the power steering pump, if its good than it will be rack and pinion issue. the pump create a high pressure to help assist with steering, and the rack and pinion work like hydraulic cylinder which receive the pressure from the pump and the steering work like control valves. by turn left or right you controling the pressure to make the wheels turn either right or left. check and see if you have any leaks.

Did you connect the Pressure side and Return side P/S couplings on the Rack, Back to Front?
Did you refill the system and Purge the Air out of the Power Steer Lines with the Engine Running, and Sweeping the Steering from Right to Left, 2 or 3 times, at the same time?
Regards,DT

Most of the time the pump will make a whining noise when used. this is a warning for a bad malfunctioning pump. if there is no noise during a hard turn, it will most likely be an issue with the steering assembly. heres a step by step guide on checking the pump.


Step1 Check the fluid levels of your vehicle first. Add power steering fluid if necessary before you proceed any further. Step2 Connect the power steering pump and hose to the pressure gauge and shutoff valve. Fit the hose to the power steering pump correctly. Make sure the shutoff valve is open before test the power steering pump. Step3 Idle the engine while turning the steering wheel all the way to the right and all the way to the left to release any air from the power steering pump. Step4 Close the shutoff valve to check system pressure for about 5 seconds. If the shutoff valve is closed longer than 5 seconds, your power steering pump can overheat and this can cause damage to the pump itself. Step5 Compare the pressure reading against the manufacturer's specifications. If the pressure is within limits, your power steering pump is working correctly and you're ready to roll. Step6 Troubleshoot if the pressure reading is not the same as the manufacturers specifications. Consult the manual for your vehicle or for your power steering pump (if you just installed a new one) to determine the source of any further problems.