Mazda 3 Front Oxygen Sensor Z601-18-861 Direct Replacement Compatible with Original Vehicle Connector

Mazda3 front oxygen sensor (OEM Z601-18-861) uses high-purity zirconia ceramic core with heat-resistant alloy housing; lifecycle tests show 100,000 km or more. Directly fits 2004-2009 Mazda3 and some Mazda5 years; no wiring adapter required. Monitors exhaust oxygen content and feeds ECU to adjust air-fuel ratio, reducing fuel consumption and emission faults. Replacement difficulty: medium; remove with oxygen sensor socket; avoid thread stripping.