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Got a check engine light with code P0420: catalyst system below efficiency threshold (bank 1). 2017 F150 2.7L Ecoboost.
Connected to OBD2 running FORscan. I am very new to all this, but I recorded a couple instances on the O2 sensors trying to capture what may be the issue. I haven't noticed any changes in engine power output, or anything strange besides maybe a little bit of a strange smell occasionally. Any advice and/or guidance would be much appreciated.
Looks like a failed or ineffective Bank 1 converter.
Notice how the B1S2 sensor oscillates a LOT as compared the B2S2? Bank 2 converter is still working while Bank 2 converter is showing very little ability to store oxygen and and then release it over time.
Bank 2 converter is still working while Bank 2 converter is showing very little ability to store oxygen and and then release it over time.
Did you mean: Bank 2 converter is still working while Bank 1 converter is showing very little…etc?
If yes, from my very limited knowledge, I would also conclude the same. I also wanted to do an oxygen storage test just to ensure that the O2 sensors are all good and the ECU is properly regulating fuel, but I was unsure how to do so safely. I’ve seen videos of people unplugging one of the intake valves to the engine, but I am nowhere near confident enough to attempt that without proper guidance.
Have after market catalytic but don’t know if it’s that. I’m uploading a link for my graphs my bottom graphs are for b1s1 and b2s1 and top graphs for B1S2 B2S2.
With many miles on the truck, and only one side failing as your Scope readout shows, the Smell indicates the Cat is not cleaning the Exhaust gas, hence the rotten egg smell that may be noted.
The TSB may or may not play a part in its failure since it applies to both sides.
The code is not an error but a failure code.
The Scope display seems to verify this.
As long as the failed Cat is not blocking exhaust flow, you will not notice much difference in engine performance because it's an Emissions failure.
Good luck.
2017 F150 P0420 Error Code
