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.

Keep in mind:

• The air pump check valve is not inspected during normal maintenance.
• A failed valve will cause the Check Engine light to turn on.
• Your car cannot pass an emissions test with a bad check valve.

How it's done:

• The air pump check valve is verified to see if it needs to be replaced
• The defective air pump check valve is removed
• The new air pump check valve is installed
• The air pump check valve is tested for operation
• The vehicle is tested to ensure proper operation of the air pump check valve

Our recommendation:

A secondary air injection system is an important part of your emissions control, and the air pump check valve is a critical component. If it fails, it’s possible for exhaust gases to escape, or for fresh air to be blocked from entering the exhaust system. If you suspect a problem with your air pump check valve, have it diagnosed and repaired by one of our expert mechanics.

What common symptoms indicate you may need to replace the Air Pump Check Valve?

• Check Engine light on with check valve failure code
• Will not pass emissions test

How important is this service?

While you won’t notice much in the way of performance degradation if the check valve fails, your Check Engine light could come on, and your car will not pass emissions testing. Because of this, you should replace a faulty air pump check valve as soon as possible.