Dorman 911-643 Secondary Air Injection Check Valve

The Dorman 911-643 Secondary Air Injection Check Valve is a direct replacement component designed to restore proper function to your vehicle's secondary air injection system. This valve prevents exhaust gases from flowing back into the air injection pump and ensures fresh air is properly delivered to the exhaust system during cold starts to reduce emissions.

Key Features:

• Direct-fit OE replacement design for reliable installation
• Durable construction engineered to withstand high exhaust temperatures and pressures
• Helps maintain proper air flow direction in the secondary air system
• Prevents backflow that can damage the air injection pump
• Essential for passing emissions testing and maintaining environmental compliance

This check valve is a critical component in vehicles equipped with secondary air injection systems, which are designed to reduce harmful emissions during engine warm-up. When the original valve fails, it can trigger check engine lights and cause the vehicle to fail emissions tests. The Dorman 911-643 provides a cost-effective solution to restore system integrity.