Where is the catalytic converter located relative to the exhaust manifold?

• A. Upstream of the exhaust manifold
• B. Within the vehicle cabin
• C. Downstream of the exhaust manifold, before the exhaust pipe
• D. Inside the engine block

Answer: (C)

Placement in the exhaust system and flow direction: The catalytic converter must sit in the exhaust stream after the engine’s exhaust manifold so it can treat the hot gases as they flow toward the tailpipe. This is downstream of the manifold, typically just after it and before the rest of the exhaust piping. Being upstream of the manifold would place it before the gases are collected from the cylinders, which would prevent proper operation. Being inside the cabin or inside the engine block would keep it away from the exhaust flow entirely, making it useless for emission control. Therefore, the correct location is downstream of the exhaust manifold, before the exhaust pipe.