Catless exhaust..Tune required?

AshtonC04

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Jul 31, 2020
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I’ve just ordered an Off-road X (Catless) From Jegs.com. Will the 02 Sensors adjust the A/F Ratio on the factory Tune? I’m aware i will get a check engine light. Just wondering if going catless on stock tune will cause damage.
 
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Bullitt95

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The upstream O2 sensors will continue to read and adjust the A:F ratio as normal but since the downstream O2 sensors will detect that there are no cats, they'll trip the CEL. You can either have the downstream O2 sensors disabled in the tune or install MIL eliminators to trick the ECU.
 

AshtonC04

New Member
Jul 31, 2020
3
0
1
16
United States
The upstream O2 sensors will continue to read and adjust the A:F ratio as normal but since the downstream O2 sensors will detect that there are no cats, they'll trip the CEL. You can either have the downstream O2 sensors disabled in the tune or install MIL eliminators to trick the ECU.
Very Helpful thank you. i’ll make sure to get some MIL eliminators
 
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