Automotive Downstream O2 Sensor Spacer with Mini Cat Converter – M18×1.5 Thread CEL Eliminator for Modified Exhaust Systems

Resolve Exhaust-Related Dashboard Warnings After System Upgrades

When you modify your vehicle's exhaust or remove emission components for off-road builds, the downstream oxygen sensor can trigger persistent dashboard warnings due to altered gas flow and temperature. This adapter spacer installs between your exhaust pipe and the rear O2 sensor, incorporating a compact internal catalytic element that normalizes sensor readings. Designed for enthusiasts working on track vehicles and off-road projects, it helps restore normal sensor operation without compromising your custom setup. The M18×1.5 threading fits most modern automotive O2 sensor ports, while the stainless steel construction resists heat and corrosion in harsh exhaust environments. Installation takes minutes with basic hand tools, and the built-in miniature converter element provides more reliable performance than simple spacer extensions.

Why You Need This

• Addresses Post-Cat Sensor Codes: Resolves common codes like P0420 and P0430 that appear after catalytic converter removal on off-road vehicles.
• Internal Converter Element: Unlike hollow spacers, the integrated mini-cat element provides more accurate sensor signal correction for consistent results.
• Corrosion-Resistant Build: SS304 stainless steel body and filter mesh withstand extreme exhaust heat and moisture without rusting or degrading over time.
• Universal M18×1.5 Fit: Standard thread size fits the majority of automotive oxygen sensor bungs used across multiple manufacturers and model years.
• Quick Installation: Simply thread the adapter into your exhaust bung, then install your O2 sensor into the adapter—no cutting, welding, or special tools required.
• Lightweight Compact Design: At just 1.4 oz, this low-profile adapter adds minimal weight and won't interfere with nearby exhaust components or chassis clearance.

Built for Off-Road Performance Projects

Whether you're building a dedicated track car, restoring a classic performance vehicle, or creating an off-road trail rig, exhaust modifications often trigger sensor faults that weren't an issue with the factory setup. This adapter is engineered specifically for motorsport and recreational use on private property, where emission regulations don't apply. The stainless steel construction endures repeated heat cycles without warping, while the mesh filter element protects the internal converter from debris. We've designed this for enthusiasts who understand their local laws and build vehicles accordingly—this component is not intended or legal for use on public roads. Every off-road project deserves reliable sensor performance, and this adapter delivers that peace of mind so you can focus on driving. With free shipping across the continental US and a 30-day return window, you can test-fit this adapter risk-free on your next build.