When turning the steering wheel, whining noise in the background can be very annoying and disturbing for any car driver. It can break your peaceful penance at the steering wheel.
Moreover, it may also signify an underlying problem, waiting to get out of control. With a range of moving parts working in tandem, it is difficult to figure out the source of such abnormal car sounds.
However, one thing you can be sure of, is that the noise, in this case, is created due to some problem in the steering wheel assembly itself. The likely candidates are the power steering pump, pulley, or the belt.
In most cars, this loud whining noise that accompanies steering, often borders on what could be described as squealing. It becomes loudest during the turn and then drops down. Here are some of the most likely causes that may lead to the noise.
Bad Power Steering Pump
Many people attribute this noise to a problem caused by a bad power steering pump. If this is the case, you will notice an increase in the degree of effort required to turn the wheel. Fluid leaks and difficulty in centering the wheel may be an indicator of a bad pump. A problem with the input shaft of the pump might also cause the noise. In either case, if you notice all these symptoms together, along with considerable noise, it is time to get the pump checked from an authorized service center.
Loose Steering Belt
The whining noise mostly arises due to a loose power steering belt. When you take a turn, the belt travels through the steering wheel pump's pulley. When it has gone loose, it does not follow its normal trajectory over the pulley but slips. This happens when the tension on it increases during a turn. That causes the whining noise.
Ergo, checking the steering belt might just help solve the mystery. To do that, you must open the hood and have a look at the power steering assembly. Check for the tension on the belt. If it's loose, just tightening the belt might solve the problem. Refer to your car manual for belt tightening instructions.
Here is a simple way to get rid of the whining noise, by tightening the steering wheel pump's belt, if that indeed is the only problem. You will need a wrench and a pry bar.
Open the car hood and locate the power steering assembly. Locate the power steering pump and adjust the arm bolt, as well as the mounting bolt connected with it. Power steering pump is always located on the engine side and is usually attached with two bolts. The upper one, which is fixed, is the mounting bolt and the lower one which is movable is the adjusting arm bolt. The lower one can usually be slid through a mounting bracket for adjustment.
To tighten the pump belt, you have to pull the steering pump away as far as possible. Loosen the adjusting arm bolt to adjust along with the mounting bolt. Pull the power steering pump away till the belt is tight enough. Once you think it's tight enough, tighten the adjusting bolt firmly using a wrench along with the mounting bolt. With that, your problem should be fixed. Otherwise, you will have to go for a change in the bearings and get the pump checked. Although the procedure is simple enough, it is still advisable that you hand the job over to a skilled mechanic.
Worn-out Pump Bearings
Another problem causing the whining might be worn pump bearings. If the whining persists, even after tightening the belt, you will have to check for worn bearings. Getting the bearings checked and replaced, is again a job best handled by professionals.
Low Levels of Power Steering Fluid
If you hear a groaning noise while turning the steering wheel, the problem might be low power steering fluid. An adequate fluid refill will cure the problem. To refill and check the fluid level, locate the reservoir cylinder. Under the hood, the power steering fluid is generally a plastic or metallic cylinder, located at the end of the steering belt. Refer to your car manual and check fluid levels. If it is below the requisite levels, it's time to replenish the reservoir. Buy the appropriate fluid recommended for your car model, and fill up the reservoir to requisite levels. Make sure to tighten the cap firmly. This should take care of the noise, if low lubrication was the causative factor.
If you hear a loud growling noise while turning, then the problem might be a defective pump, problems in the steering gear assembly, or worn out wheel bearings. Other than that, the bit of hissing noise that you may hear while turning is normal. If none of the analysis and pointers presented above are helpful, it is time to call in an automobile professional.