Question about 2002 Toyota RAV4

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Code PO42O and PO43O ? Anyone know what they

Code PO42O and PO43O ? Anyone know what they mean?
for Rav4 2002

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The meaning of: P0420 Catalyst System Efficiency Below Threshold on Bank 1 P0430 Catalyst System Efficiency Below Threshold on Bank 2

Basically the Oxygen sensors ( one before and one after the catalytic converter ) have abnormal readings from the exhaust. Further diagnosing will need to be done by a mechanic to find the source of the problem. The possibilities could be the O2 sensors themselves, a leak in the exhaust manifold, a bad catalytic converter, and etc.

Posted on Nov 14, 2009

  • Christine Parker
    Christine Parker Mar 19, 2013

    thanks to all suggestions



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How do i repair a p0420 code

this indicates the catalytic convertor isn't working at correct values , this may be due to a leak in the air intake system or the exhaust system before the cat convertor , if no leaks found i'd recommend a fuel addative that cleans the catalytic convertor as well as the engine parts , take for a longish drive (50-100) at a highish speed to get to a high engine temperature , may have to do this a couple of times and rescan for code , if still showing code will need further investigation as to which sensor may need replacing

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