BMW 525i Car Air Pump Check Valve Replacement at your home or office.

What is the Air Pump Check Valve all about?

In a secondary air injection system, air must be injected into the exhaust system, but exhaust fumes must not be able to escape. This is accomplished by using a one-way air pump check valve. Think of it as a one-way street -- air can enter, but exhaust gases can't leave.

These secondary injection systems are used to ensure a fuller burn of spent exhaust gases, which both improves fuel economy and eliminates pollution from the vehicle exhaust. It’s an important part of your emissions system. Generally, the air pump check valve is mounted near the top passenger side of the engine, although this can vary. Some vehicles have more than one check valve, as well.

Over time, the air pump check valve is subject to not only high heat, but also other forms of damage. It can deteriorate and degrade. While there is no set lifespan for these components, they can and do fail.