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Secondary Air Injection System

Due to over-enrichment of the mixture during cold start, an increased amount of unburned hydrocarbons exists in the exhaust gas. Injection of secondary air improves oxidation in the catalytic converter, speeding up start-up time for catalytic converter, and reducing emissions during cold start-up.

Secondary air injection system components include:

To test secondary Air Injection (AIR) system components, see secondary AIR related DTC(s) under DIAGNOSTIC TROUBLE CODE DEFINITIONS in appropriate SELF-DIAGNOSTICS article.