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Posted

I'm having some MPG issues that I can't pinpoint. 16 Sierra DC A/T, 6speed, 5.3, 3.42's, leveled 3.5" with LT285/65R20's. Stock drivetrain. About 20k miles now with this setup, MPG ranging from 15.5-16.8, avg 15.8. I'm ok with this, but -

 

Added an Airaid MIT tube and filter last week. Now getting 14.0-14.4 best. Same driving manners, same environment. 30 mile commute daily, 75% highway. What gives?

Posted

Well if the Airaid filter is letting in more air then that means the engine needs more fuel. I would keep the MIT and put a stock filter back in. It will feel the same.

I will try that. I also cleared readiness codes, fuel trims, etc to try and relearn but no change

 

 

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Posted

Did you disconnect the battery and let it sit for 10-20mins?

 

I put my MIT on and my mileage took a hit. Had to disconnect battery to do a relearn process and all

Is good now.

Posted

Did you disconnect the battery and let it sit for 10-20mins?

 

I put my MIT on and my mileage took a hit. Had to disconnect battery to do a relearn process and all

Is good now.

Yes I went in with my tech2 and reset everything,

 

 

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Posted

Yes I went in with my tech2 and reset everything,

 

 

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On a stock tune with my 2017 6.2 adding an Air-raid full kit increased my MPG a solid 2 MPG. I went from 16.2 to 18.3. It seems to me that some how the ECM is not making the proper air fuel adjustment. I have heard that resetting the battery does nothing but you have used the tech2. Hmm have you thought about getting a custom in-person tune done with wide-band hooked up. Then you would be able to take full advantage of that extra air coming in. I'm 99% sure that would do it but you should not need it. Like I was saying I had a 2 MPG increase even before I got a tune.

 

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Posted

On a stock tune with my 2017 6.2 adding an Air-raid full kit increased my MPG a solid 2 MPG. I went from 16.2 to 18.3. It seems to me that some how the ECM is not making the proper air fuel adjustment. I have heard that resetting the battery does nothing but you have used the tech2. Hmm have you thought about getting a custom in-person tune done with wide-band hooked up. Then you would be able to take full advantage of that extra air coming in. I'm 99% sure that would do it but you should not need it. Like I was saying I had a 2 MPG increase even before I got a tune.

 

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I plan to go the black bear route with an exhaust at some point. I thought it would be the same or better, never thought it would drop that much with a simple MIT. I guess I'll have to make some choices now

 

 

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Posted

I plan to go the black bear route with an exhaust at some point. I thought it would be the same or better, never thought it would drop that much with a simple MIT. I guess I'll have to make some choices now

 

 

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You got me scratching my head as well. Get your exhaust and and then get it tuned and I'm sure your problem would be solved.

 

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Posted

I'm having some MPG issues that I can't pinpoint. 16 Sierra DC A/T, 6speed, 5.3, 3.42's, leveled 3.5" with LT285/65R20's. Stock drivetrain. About 20k miles now with this setup, MPG ranging from 15.5-16.8, avg 15.8. I'm ok with this, but -

 

Added an Airaid MIT tube and filter last week. Now getting 14.0-14.4 best. Same driving manners, same environment. 30 mile commute daily, 75% highway. What gives?

Let's see pics of truck!

 

 

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Posted

Let's see pics of truck!

 

 

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2ba094cddeec5228974d0e36bf03cbb8.jpg

 

9efc74d12242097aca6ac05b6702bde5.jpg

 

0011de471c4acb4354195e84c284acfb.jpg

 

 

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Posted
On 10/9/2017 at 2:41 PM, TheMekanik said:

I'm having some MPG issues that I can't pinpoint. 16 Sierra DC A/T, 6speed, 5.3, 3.42's, leveled 3.5" with LT285/65R20's. Stock drivetrain. About 20k miles now with this setup, MPG ranging from 15.5-16.8, avg 15.8. I'm ok with this, but -

 

Added an Airaid MIT tube and filter last week. Now getting 14.0-14.4 best. Same driving manners, same environment. 30 mile commute daily, 75% highway. What gives?

My '15 Silverado LTZ Z71 (2WD) is pretty much set up the same, I've been averaging 19.3, since I bought it (according to "Trip B," never reset). 20 mile commute to/from work, and 25 miles to/from church.  I've taken a few trips to/from San Diego, don't remember what I got on those trips.  Tuesday morning, I left work, drove to Home Depot in Tehachapi (48 miles), and then home (31 miles).  Left work with "Trip A" (reset at every refuel) showing 18.5MPG (been remote starting it as soon as I leave the hangar or my front door, been cold lately going to/from work), got to Home Depot with 18.3 showing, and got home with 19.5.

 

Crossed the 40K mark Sunday afternoon.

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