Oxygen Sensors
Ford Ranger
Ford Ranger XL
Ford Ranger XLT

How many oxygen sensor on a 99 ford ranger ext cab 4x4 front and back?



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On the 3.0 L and 4.0 L there are 2 oxygen sensors at the front and 1 oxygen sensor (which monitors your catalytic convertor efficiency) at the back after the exhaust gasses have passed through the convertor. On the four cylinder engine - 1 oxygen sensor at the front - 1 oxygen sensor at the back (downstream of catalytic convertor - monitors catalytic convertor efficiency) Helpfull