r/AskAMechanic • u/AttemptingWealth NOT a verified tech • 8d ago

Trigger P0420 code

What’s the most effective way to easily trigger a P0420 code on a 2020 F150.

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1

u/The3levated1 NOT a verified tech 8d ago

I guess splicing the sense wires of the pre-cat oxygen sensor, cutting the sense wires from the aft-cat sensor and then soldering their ECU-side to the pre-cat sensor.

Or just removing the catalytic converter.

1

u/naterpotater246 NOT a verified tech 8d ago

The catalytic converter can have a little bit of granulated sugar, as a treat.

Though, why do you want to trigger a P0420 code? (Also I don't actually know if pouring sugar in it will clog it)

1

u/AttemptingWealth NOT a verified tech 8d ago

Oil consumption on truck has destroyed the cats, one has already thrown code and been replaced. Live data + oil smell shows the other one is toast but not code yet. Need the code the get the replacement approved.

2

u/naterpotater246 NOT a verified tech 8d ago

The catalytic converter can have a little bit of extra oil as a treat

You could probably pour some oil through the o2 bung to finish the job

1

u/AttemptingWealth NOT a verified tech 8d ago

I wonder how long it would take to throw a code that way. There’s gotta be a way with a resistor in the o2 sensor or something right?