Engine covers were once cosmetic items intended to clean up the appearance under the hood. The thin plastic cover hid wires, injectors and coils from the vehicle owner. But with the introduction of gasoline direct injection, these covers help to absorb the noise generated by the high-pressure fuel pump. Forgetting to reinstall a cover can cause a customer complaint of a noise engine.
Engine covers are no longer just cosmetic. This video is sponsored by Auto Value & Bumper To Bumper.