Dorman 673-931 Catalytic Converter with Integrated Exhaust Manifold - Left

OE-Style Manifold Converter for Cadillac STS

Dorman 673-931 is a catalytic converter with integrated exhaust manifold built for direct replacement on specific Cadillac applications. It combines the manifold and converter in one assembly, with CARB certification for the listed vehicle fitment and OE-style construction for a precise match.

• Fits 2005-2006 Cadillac STS, left
• CARB certified with Executive Order D-665-17
• Cast iron converter body with natural finish
• Round inlet port shape
• Includes inlet gasket and outlet mounting hardware
• Package contents include exhaust manifold, input gasket, output flange, nuts, and studs

Detailed Product Overview

This Dorman 673-931 manifold converter is engineered to match the original equipment layout on the specified Cadillac STS left-side application. It is a direct-fit exhaust replacement for 2005-2006 Cadillac STS models with LEV Emissions Level 1 and CARB compliance requirements, helping restore the factory-style exhaust manifold and catalytic converter assembly in one unit. The cast iron body supports durability in high-heat exhaust service, while the integrated design simplifies replacement of the manifold and converter section together.

This part cross-references GM 12567687 for the same application.

Common Problems It Can Address

• Failed catalytic converter efficiency on the left-side exhaust bank
• Cracked or leaking exhaust manifold assembly
• Exhaust odor or emissions test failure related to converter performance
• Check engine light conditions tied to catalyst or exhaust flow faults
• Noise from manifold or flange leakage at the exhaust connection

Installation Notes and Tips

Verify the vehicle is a 2005-2006 Cadillac STS, left-side application before installation. Confirm the inlet port shape, outlet mounting hole count, and flange alignment against the original part to ensure proper fit. Replace damaged sealing surfaces and follow factory torque specifications during installation. Because this is a CARB-certified exhaust component, confirm local emissions requirements before service.

Quality Assurance

Dorman manufactures this manifold converter to match original equipment dimensions and emissions-related requirements for the listed application. CARB certification and Executive Order D-665-17 identify it for use on the specified California-compliant fitment.