The air pump check valve is a one way valve that allows air from the air pump to enter the exhaust system.
Symptoms of Wear or Failure
- Check Engine Light may illuminate
- Vehicle may fail an emissions inspection
Related Repair Advice
- An air injection system trouble code isn't always triggered by a defective air pump check valve. It can also be triggered by a restricted passage or air pipe, a defective air pump, an air pump relay failure, or a wiring problem.
- On a v-type engine with two check valves, it is often recommended to replace both check valves if a trouble code is set indicating the failure of one. The "good" valve may already be partially restricted, but not yet setting a trouble code.