Mazda Haima Rear Oxygen Sensor HC00-18-861BM1A Universal Fits Many

This post-oxygen sensor replacement OEM HC00-18-861B has strong universality and directly replaces OEM parts on Mazda and Haima vehicles. Function: monitor oxygen content in exhaust and feed ECU to adjust air-fuel ratio, ensuring engine combustion efficiency. Compatible with Mazda 323, Haima Futura, Prima, and Haima Futura, Haima 3, etc. After installation, it can resolve high fuel consumption, exhaust overages, and engine fault lights. If the car shows sluggish acceleration, unstable idle, or black exhaust smoke, it’s basically aged post-oxygen sensor; replacing early saves fuel.