Posts Tagged: P0491 Secondary Air Injection

P0491 trouble code Chrysler

What causes a P0491 trouble code in a Chrysler Trouble code P0491 trouble code is defined as Secondary Air Injection Excess/Insufficient Air Flow. This code is triggered when the Engine Control Module (ECM) detects that there is not enough air being pumped into the exhaust system to help reduce emissions. The secondary air injection system is designed to pump fresh air into the exhaust stream to help burn off excess hydrocarbons and carbon monoxide before they reach the catalytic converter. To understand the purpose of the secondary air system and … Read More