Catalyst System Bank 1 Low Efficiency
Possible Causes:Air leaks at the exhaust manifold or in the exhaust pipesBase engine problems (i.e., high engine oil or coolant usage).Catalytic converter is damaged, contaminated or has failed.Continuous engine misfire conditions, or weak or low coil output.Front HO2S or rear HO2S is contaminated with fuel or moisture.Rear HO2S is loose in the mounting hole (check it for a leak).Front HO2S older (aged) than the rear HO2S (HO2S-12 is lazy).Click here to see.
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