engine code
#1
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po 420 low catalyst efficency code, can anyone tell me which side this is on, I think it's on the driver side since I just changed the passenger side, they are random tech high flow cat's, can it also be a bad sensor.
#2
TECH Senior Member
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DTC P0420 Catalyst System Low Efficiency Bank 1
Driver side
Could be a bad sensor... or more than likely the high flow cat's aren't cleaning up the exhaust as well as the stockers so the PCM is seeing this and getting itself worked up.
Driver side
Could be a bad sensor... or more than likely the high flow cat's aren't cleaning up the exhaust as well as the stockers so the PCM is seeing this and getting itself worked up.
#3
TECH Enthusiast
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Um the high flow cats wouldnt clean up the exhaust as well as the stock? So would buying aftermarket cats like magna be a bad move? Or would 02 simms fix the job.?