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Think your vehicle’s power steering pump may be bad? Read through our guide below, which includes common symptoms, and tips on how to address the issue.

What are the Signs of a Bad Power Steering Pump?

Like any other component, the power steering pump is prone to wear and tear. It’s important to diagnose (and address) a failing power steering pump, as it can worsen the overall handling of your vehicle. Any sudden changes in the steering behavior can be hazardous and possibly put you and your passengers at risk.

Below are the most common telltale signs of a bad power steering pump:

Whining noise that coincides with engine speed

Among the common faulty power steering pump symptoms are whining noises that coincide with engine speed. The power steering pump is driven off the engine via a belt. If you have a bad pump, it could whine the moment you turn your engine on. The pitch often gets higher as your RPM climbs up and/or when you’re turning the steering wheel, and you may feel a jerking sensation in the wheel. If your car exhibits this symptoms, make sure to check the fluid first.

Whining noises are often caused by a low fluid level or worn out pump. Since more than one issue can cause whining noises, it is wise not to jump to conclusions; else you might spend unnecessary time and money.

woman's hand on a steering wheel with power steering enabled
The power steering pump is responsible for providing the hydraulic pressure needed for the system to function properly.

Diagnosing and Fixing Whining Noises

To reiterate, let’s establish the fact that a whining noise isn’t always the power steering. It can also be a bad bearing on another component or, in rare cases, a faulty belt may cause whining noises that sound like a power steering pump. If your steering seems to be working normally and you don’t hear the whining noise change when you turn the wheels and the pump isn’t low on fluid, remove the belt(s) and check all the other belt-driven components for roughness, play, etc. before condemning the power steering pump. Replacing the pump sometimes takes a special puller to remove and install the pulley because the new pump often comes without one.

Sometimes a power steering system can become air-bound if the fluid overheats (there’s a power steering fluid cooler) and the air trapped in the fluid can cause the power steering pump to make whining noises.

GM released a TSB on this very issue along with a special tool to connect to the power steering fill neck so you can apply vacuum to the power steering system while turning the wheels back and forth with the front end raised to work the air out. During these maneuvers, the air bubbles will rise out of the system due to the vacuum applied to the fill port.

The video below provides a short demonstration of that procedure, which is also useful in bleeding the power steering system after replacing components. Be careful not to turn the wheels back and forth a lot when the car isn’t moving, because it stresses steering parts in a big way.

Power Steering systems with remote fluid reservoirs (not built onto the pump) have a screen in the bottom of the reservoir that can clog (and sometimes does), and if you can draw the fluid out to the point that you can see that the screen is clogged, just cleaning that screen will take care of a whining power steering pump.

If you still have power steering noise after some sensible checking, you might need professional help. It’s advisable to bring your car to a certified mechanic, who is far more capable of performing the necessary tests and evaluation.

Loss of power assist

Have you had that experience where your car felt like it reverted to manual steering? This is a clear indication that your power steering is not working. The power steering pump is among the first components you should check if the steering wheel becomes very difficult to turn.

The pump is responsible for making sure the fluid is being circulated properly under pressure. If the pump ceases operation, the pressure needed will not be regulated and the steering wheel would feel a lot heavier to operate.

Sometimes the power steering pump will fail without making a sound. It may be very quiet and full of fluid, while not providing pressure to the steering gear. In that case, the pump is bad.

Some vehicles with Variable Assist Power Steering (VAPS) may default to a stiff steering when that system develops a fault. VAPS (there are other names depending on the OEM) provides less assist at highway speeds than during parking lot maneuvers, and if it malfunctions, the VAPS system might be at fault. Have it checked by a pro if you believe that’s the case.

Fluid leaks

Power steering pumps also have seals that can develop leaks, which then creates a low fluid level. If you suspect a bad power steering pump, consider checking for leaks.

Low power steering fluid can damage the pump and cause it to make weird noises. The most common low power steering fluid symptoms are jerky steering feedback and a stiff steering wheel.

You can prevent further problems by tracing a leak early.

Power steering fluid leak symptoms include red or light brown puddle formations underneath your car. This is the easiest way to find out whether your power steering pump is leaking fluid. However, a bad steering pump doesn’t always involve a leak.

power steering fluid leak under a car
Check for leaks if you suspect a faulty power steering pump.

Metal contamination to the fluid

It is important for the power steering system to be tightly sealed to maintain and achieve the pressure it needs to operate. But even when the fluid is completely protected from external elements, it can still be contaminated by small debris.

And where would the debris come from, you ask? From inside the power steering pump.

If the pump is extremely damaged, metal parts inside can come apart and mix with the power steering fluid. The tiny metal shards can damage passages and cause the whole power steering system to fail. Of course, if this happens, the pump usually needs replacing anyway, and the steering gear may need replacing as well, along with a system flush.

Can You Drive Without Power Steering?

The short answer is you shouldn’t—even if you can. You may find some people arguing that cars back then were power assist-free, so driving around without power steering shouldn’t be a concern.

The caster angles on cars without power steering are set to make the vehicle easier to steer, but the vehicle had less steering stability with those angles. So while it’s true that older cars didn’t have power steering, driving without it has various consequences, some of which are listed below.

Difficulty steering

A failed power steering pump can make your vehicle difficult to steer. Obviously, such a scenario presents a safety concern.

A leak that worsens through time

Not dealing with a problem will definitely make it worse. Power steering fluid is a hydraulic fluid meant to be contained in a tightly sealed system. If it leaks, your power steering will be compromised.

A small leak may sound unalarming but once it gets big, especially if it’s due to a crack somewhere along the steering lines, problems will quickly unfold.

An existing leak could be causing your power steering pump to fail. If this small leak rapidly turns into an uncontrollable mess, you could end up damaging the pump and other parts of the power steering system. When this happens, a more costly repair and replacement will be your only option.

A badly damaged power steering pump

Your steering pump creates pressure to help regulate the power steering fluid. Even very minor damage can quickly compromise its ability to do this.

This is the perfect time to act and consult a certified mechanic if the pump is still serviceable. If the problem gets worse, you may end up completely damaging other components, such as the steering gear, beyond repair.

close up shot of a damaged power steering pump and wrench
There are three types of power steering systems: hydraulic, electro-hydraulic, and fully electric.

What is a Power Steering Pump?

The power steering pump is responsible for providing the hydraulic pressure needed for the system to function properly. It regulates the power steering fluid, which helps make the steering lighter and easier to operate. It is connected to your engine via a belt-pulley mechanism that’s driven off the crankshaft.

There are different types of power steering pumps, known as the rotary vane, roller, and slipper. Though each one features different designs and mechanisms, all three function on the same principle, and that is to pump the fluid to the entire system.

An average vehicle weighs about 2,900 pounds. That, of course, will vary depending on what type of vehicle you’re driving. On average, a midsize car can weigh up to 3,400 pounds, while a large pickup truck can weigh twice as much. Simply put, cars are heavy. But thanks to power steering, you’re able to drive around effortlessly—even at low speeds.

There are three types of power steering systems: hydraulic, electro-hydraulic, and fully electric. Hydraulic systems use a pump to circulate the fluid under pressure, while the latter relies solely on a motor. The first two use an incompressible fluid that converts mechanical force into fluid power as it gets pressurized.

Products Mentioned in this Guide

Any information provided on this Website is for informational purposes only and is not intended to replace consultation with a professional mechanic.

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Larry Wayne Douglas

The power steering pump container that holds the power steering fluid has a leak where it plugged in to the return line The Jug is leaking

CarParts.com

Hi Larry,

There is probably a seal between the line and the reservoir that’s leaking. If you tell me the year, make, and model of your vehicle, I can look into it for you.

Lyle Harnois

Can you tell me where the ps reservoir is on a 2001 Mercedes’ s500 w220? Show me a picture of location and email me please

Lyle harnois

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