2021 ESS G3 w/ LT and cats - won't get past readiness for emissions

Bizarro

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I apologize for the dumb question and I tried to do a search cause I'm sure this has probably been discussed a thousand times. But didn't find anything significant other than "are you ready to deploy to the Ukraine" smh

I have a 2021 Mach 1 with an ESS G3, long tubes and cats. No codes, no other issues...just won't pass the Readiness portion.
I guess my question is, can I revert the tune back to stock (obviously leaving the SC in place) and take easy driving it to get it past the Readiness.
Or is there actually something in the tune that can be looked at to get past this issue.
 

01yellercobra

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I'm going to guess you're not running stock injectors or MAF. Those two would make it impossible to go back to a stock tune unless you swapped them out. Best bet would be to talk to your tuner.
 

Bizarro

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I'm going to guess you're not running stock injectors or MAF. Those two would make it impossible to go back to a stock tune unless you swapped them out. Best bet would be to talk to your tuner.
Yep...as soon as I started reading your response and got to "Injectors", I was like...."I'm an idiot". lol

I'm going to try talking to the tuner (previous owner had the car tuned). If he's not willing to do anything, which I wouldn't be overly surprised, I'll switch tuners....was really just trying not to have to tun again for this stupid of a reason.
 

FourSixPony

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Yep...as soon as I started reading your response and got to "Injectors", I was like...."I'm an idiot". lol

I'm going to try talking to the tuner (previous owner had the car tuned). If he's not willing to do anything, which I wouldn't be overly surprised, I'll switch tuners....was really just trying not to have to tun again for this stupid of a reason.

Who was the car tuned by? They are the only ones who can help you at this point.
 

Deceptive

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1. You mentioned it has longtubes so I am assuming aftermarket midpipe with high flow cats. Do you have something to help eliminate the known “cat inefficiency” issue because of this?

2. How are you driving the car? There is a certain way these need to be driven to set the monitors. I believe it is usually a couple hundred miles.

3. While the tuner should no longer have the ability to turn stuff off, I’d ask if anything was.


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decipha

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You can't pull codes correctly on a modified tune since no telling what the tuner disabled.

Stock tune would be upset with long tubes since the o2's are farther back.

There could be any number of reasons why it wont set it. Most common is that the tuner disabled the rear o2s, disabled the checks or didn't adjust the monitors correctly.

If the car is not a daily driver you can yank the ecu out and ship it to any reputable tuner who can plug in directly and re-enable it no problem. Would be much easier if your tuner does it for you though.

If you get in a bind LMK.
 

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