Code P0420 Catalyst System Efficiency Below Threshold bank 1
So my CEl light came on and I hooked up the scanner and got the above code. Question is would a leaky center muffler cause it? The muffler is still quiet and I did take the car to a shop and they looked at it and sad that only the outer shell was rusted and I probably have another year of use....
What other issues could cause the problem??
TIA
What other issues could cause the problem??
TIA
yes common causes are vacuum leaks and exhaust leaks. A bad O2 sensor can also do the same. Its also common to get such faults when using low quality or incorrect after market parts (sensitivity varies by model and year)
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