Do you have a check engine light for a secondary O2 sensor/Catalyst below threshold? Used in conjunction with our down pipe or turbo back system this little guy will do the trick if you are getting a P0420 check engine code. We recommend starting with the smallest size jet.

Getting rid of a CEL can be more art than science... by causing less exhaust gas exposure to the O2 sensor, it can be "fooled" to think the catalytic converter is "doing it's job" and the CEL may not be illuminated. There is no rule of thumb as to how much gas exposure reduction will accomplish this goal. Before installing, the car's error codes should be reset so that the CEL is not illuminated.

The "J" shape allows the O2 sensor to be installed parallel to the exhaust pipe for better clearance.

No-weld design. It simply screws in to your existing O2 sensor bung, and you then screw your O2 sensor in to the other end of the fitting.


OFF ROAD USE NOTICE: items sold through Krona Performance including  exhaust systems and hardware are designed for off-road/race use only, and are not applicable for vehicles in states that require pollution controlled vehicles. California (CARB) & other states prohibit the sale or use of some aftermarket parts, including those that tamper with, modify or defeat emissions systems in any 1966 and newer vehicles. Krona Performance prohibits the use of these products on emission controlled roads. These parts are sold for OFF ROAD, RACE-ONLY, ground-vehicle use only controlled environment.

Krona Peformance does not implicitly or explicitly confirm the legality of using any products it sells on public roads, that is entirely the responsibility of the consumer.


WARNING: Cancer and Reproductive Harm -

J Style Oxygen Sensor Thread On Restrictor Fitting


If you are placing an order outside of the United States, please contact us before completing your order.