Where would your power steering system be without power? Supplying that power is the responsibility of your BMW Power Steering Pump —well, your engine actually supplies the power, but it’s transferred to hydraulic pressure thanks to the power steering pump. Hundreds of psi worth of fluid pressure is required to give full assist when you crank your car’s steering wheel, particularly when your car is sitting still. The vane-type rotary pump inside your BMW power steering pump supplies all that pressure, and routes it to the steering rack through a high-pressure fluid line.

When a BMW power steering pump goes bad, it’s usually due to leakage, either internal or external. Internal leaks are difficult to spot, but they manifest themselves through groaning noises and “flat spots” in your steering assist. External leaks are much easier to find. If you have to replace power steering fluid frequently, check the back of your BMW power steering pump and the high-pressure hose. Chances are you’ll find a stream of brown or pinkish fluid somewhere nearby.