Review on 🔌 Denso 234-4209 Oxygen Sensor with Connectors (not included) by Robert Hunter

With extensive automotive experience, I only use Denso O2 sensors. This was supposed to be a replacement for the second bottom sensor on my Acura Integra. (upper (main) O2 sensor is new, Denso too) The process of replacing the lower sensor is much deeper. After doing further research after placing my order, I found that if there is no engine code/check engine light, the bottom thread does not need to be replaced. Downstream just checks that the catalyst is working properly. An old still working "primary" O2 sensor (responsible for fuel enrichment) say over 100,000 miles can improve performance/fuel economy. While the claim is negotiable or maybe subtle my cars are very well maintained while at 177k I thought it was worth it. All Denso O2 sensors I have covered are assembled in the USA using foreign parts.