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O2 Sensors?

BrooseDaMoose

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#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!
 

2020FordRaptor

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#2
Do you have defoulers on?
 

OP
BrooseDaMoose

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

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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2020FordRaptor

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#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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BrooseDaMoose

BrooseDaMoose

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Thread Starter #8
Got lucky, some people have, you need the defoulers nonetheless.
Yep, exactly right! They emailed me back and said I was lucky I went almost two years. They are going to send me a set of defoulers for free. I think that’s pretty cool of them!


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BrooseDaMoose
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Thread Starter #9
I got the defoulers and installed them. Cleared the code and as soon as I started driving, the CEL came back on. Now I have a P0141 (Heater Circuit) code! Thought maybe it was just the connector so I tried pressing it together but that didn't work. When I tried to pull the connector apart it wouldn't budge! I can't get the damn thing apart! I took it to my mechanic and he tried and couldn't get it apart either. Unfortunately he was busy so he couldn't spend time messing with it. I've been laying on my back for about a half hour trying to get it apart but it just won't budge! At the moment I'm thinking about just getting a couple new sensors and then just cutting the stuck connector on the sensor side and prying it off. I just don't want to damage the vehicle side! Any ideas on how to get it apart?
 



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