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Discussion Starter · #1 ·
I have been chasing down an annoying issue I've had for sometime where at idle I can hear and lightly feel the engine stumble almost like its missing. The stumbles/misses aren't following any consistent pattern and go away with anything more than very very light throttle application. From a drivability standpoint all I notice is sometimes a brief hesitation when rpms dip low during initial acceleration from stop. This happens while cold and warm in all weather conditions. No codes found.

In trying to diagnose this, I swapped my intake from the green filter and open box back to stock config thinking I would be able to better hear the issue without the intake noise. I actually found that this alone resolved the issue. Testing it, I swapped back and the problem re appeared. Taking the next step I tried Green filter WITH the lid and also saw the issue. Stock filter and closed lid seems to be the only good configuration.

Has anyone else had a similar issue and or fixed it by going back to the stock intake configuration? Could it be a difference in filter air flow impedance?

For reference, I am running the FRPP tune (new revision) and have a CNT catback. Other than that I am stock.

Thanks
 

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I have had the green filter for probably, IDK, 10K miles. If not more. I have had the air box lid off longer than that. And I have not had any drive-ability concerns with my engine.

I have a Accessport though, IDK if that makes a difference.
 

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Discussion Starter · #6 ·
What year cars? My 13 never had an issue with an aftermarket filter. I ran a Cobb branded Green Filter since day one.

Sent from another garage.
15' here. Due to the FRPP tune needing a laptop and additional software to flash back to stock I have avoided testing on the stock tune. I would imagine it is something that a custom tune or maybe OTS tunes can address.


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There's a guy on here that started a thread about a 2+ mpg loss after installing a green filter. I pimped him on the thread if he ever got it figured out, but he never came back and followed up.
 

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Discussion Starter · #8 ·
There's a guy on here that started a thread about a 2+ mpg loss after installing a green filter. I pimped him on the thread if he ever got it figured out, but he never came back and followed up.
Just got the Torque Pro app set up to log. Going to try and get some numbers to see if there is any measurable difference. Any recommendations on what parameters to log?


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I have a 16 and installed the Green filter and RS air box lid at 700 miles. I'm currently at 1900 miles and no driveability or fuel economy issues.
 

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I have a 14 that does that but only at cold start . No codes and running Cobb stage 1 and I did notice a mpg drop at least according to the cars mpg display
 
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