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O2 Sensors?

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East Freetown, MA
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2020 Explorer ST, Silver Spruce Metalic
#1
I got a check engine light so I pulled the code and it read P0420/$07ES which is "Catalyst System Efficiency Below Threshold (Bank 1)". I have the SPD downpipes which are only two years old. Could this just be an O2 sensor? I figure I would get a code for it if it was. I ran a live view and the O2 sensors are showing the same value on both sides. Kinda scratching my head here. I can't imagine the cat would have gone bad in two years!
 

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'20 Raptor, '22 Explorer ST, '14 GT500, '03 F150
#2
Do you have defoulers on?
 

OP
BrooseDaMoose
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Thread Starter #3
No defoulers.


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Cruising68

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#4
Following. I have over a year on my spd’s. No problems so far. How many miles? 50k or more you might have a lazy O2 sensor. Efficiency is usually post cat sensors. I will say dropping the spd’s should be way easier than the oem cats. You might even be able to get to the downstream sensors without dropping them. Could also swap left and right sensors to see if it follows the sensor. Not sure if there are unique left and right sensors.


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BrooseDaMoose
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Thread Starter #6
I got a message in to SPD about it. I don’t understand why they have worked for two years and 20K miles without defoulers. Sensors have 51K on them so I’m going to change them and I’ll add the defoulers at the same time. Might as well.


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Messages
2,226
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1,030
Points
252
Location
Nevada
Vehicle
'20 Raptor, '22 Explorer ST, '14 GT500, '03 F150
#7
I got a message in to SPD about it. I don’t understand why they have worked for two years and 20K miles without defoulers. Sensors have 51K on them so I’m going to change them and I’ll add the defoulers at the same time. Might as well.


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Got lucky, some people have, you need the defoulers nonetheless.
 



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