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Oxygen sensor defouler?

iso100

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#1
I'm interested in getting a downpipe but don't want to have to look at a CEL all the time. I'm also not ready for an intercooler so a stage 3 tune that turns off the CEL isn't an option.

Have any of you run an O2 defouler and successfully avoided the CEL?

Are there any adverse effects to using one like incorrect readings, etc?
 


airjor13

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#2
I'm interested in getting a downpipe but don't want to have to look at a CEL all the time. I'm also not ready for an intercooler so a stage 3 tune that turns off the CEL isn't an option.

Have any of you run an O2 defouler and successfully avoided the CEL?

Are there any adverse effects to using one like incorrect readings, etc?
I been running the stg 3 OTS 93 without an aftermarket intercooler for a while now, since v103 came out, its been fine so far for daily driving, but the charged air temp does get up rather high if your a doing prolonged spirited drive (~+15-20 degrees ambient). I think you will be fine as long as your not doing track days man, and getting rid of that CEL is a huge plus because of the eye sore.
 


Sourskittle

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#3
I've had it since like Jan.
3 cel since then. Ap resets it and its another 2-3 months without an issue
 


OP
I

iso100

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Thread Starter #4
Ahh, it's that infrequent? What downpipe do you have and with cat?
 


OP
I

iso100

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Thread Starter #5
Guess I should have specified that I would be running a cat.
 


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Broomfield
#7
Yeah I ran a defouler for about 5 months. No CEL ever. Took it out bevause I got custom tuned and it's programmed not to show a cel for the downpipe
 


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Broomfield
#8
If your running a cat then you don't need one. From what I understand the defouler tricks your car into thinking it has a cat?
 


rooSTer

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#9
From what I understand the defouler tricks your car into thinking it has a cat?
Somewhat, its to trick your computer to thinking there is an o2 sensor whenever you delete an o2 sensor.
 


JPGC

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#10
I contacted Ian at Cobb a few weeks ago about this and he stated that the rear o2 sensor has the ability to make up to 20 percent fuel correction and that they would not recommend using a defouler. Take that for what it's worth as I was asking them to decide wether I should get the Accesstuner race software or not. I ended up getting the software and just removing the code on my stag 1.
 




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