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Discussion Starter · #1 ·
I just replaced my stock filter with a Green filter and my HWY MPG dropped from 34 --> 26. Is this normal? Is the CPU just freaking out now? Any way to correct this?

Thanks!
 

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Discussion Starter · #3 ·

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The ECU wont "freak out" due to a simple filter change. When you put in the filter, what were you're driving habits like? Have you hooned around town with it in? Did it get super cold? Did you change up fuel.
 

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Discussion Starter · #5 ·
The ECU wont "freak out" due to a simple filter change. When you put in the filter, what were you're driving habits like? Have you hooned around town with it in? Did it get super cold? Did you change up fuel.
All factors are equal. Didn't change habits. Still cruzing around 70-75mph on the hwy. same Costco premium. Air temp between 55-60 degrees.
 

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Are you going by the computer MPG estimate numbers? If so how many miles since you reset the MPG average.

34-26 is a pretty drastic change so those numbers do not look accurate to me. I would run a tank thru the car and do a manual calculation at next fill up. Compare that number to your normal MPG average. Pretty sure it will be in line with what you normally get or only off by 1-2.
 

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Discussion Starter · #8 ·
Are you going by the computer MPG estimate numbers? If so how many miles since you reset the MPG average.

34-26 is a pretty drastic change so those numbers do not look accurate to me. I would run a tank thru the car and do a manual calculation at next fill up. Compare that number to your normal MPG average. Pretty sure it will be in line with what you normally get or only off by 1-2.
You're car is still pretty new. Do a fill fresh fill up from E and see what happens.
When I added my filter, my MPG went up 1-3 pts.
Will do. I'll clear through this tank and see how it goes from there

Yes I was keeping an eye on the instant mpg as I always do and noticed the decrease
 

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First I would be happy to get 26mpg. I have stayed at 25.4 for the past 7000 miles.

Second, if you were getting 34mpg and the only thing you changed was the filter, put the stock filter back in dude!
 

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Discussion Starter · #15 ·
Oil, fuel quality, tires and road conditions are all factory id milage. When I was getting mid 30s I set my cruise at 65 and had a set of Kumho 4X all seasons in 235/40/18. Also changed to Mobil 1 Full Synthetic. Now I get low 30s due to mods and summer tires.

Sent from another garage.
Did you notice better mpg with full synthetic? This is my daily and I'm trying to get the best possible lol
 

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Good oil, good maintenance, tires, etc, are all true factors in fuel economy...yes. But they are not enough alone to drive this car into the mid/upper 30's on fuel mileage. To even come close to that, you'd have to immediately leave the gas station, enter the freeway, not encounter any hills or traffic, drive way under 70, and not get off the freeway until you were out of gas. Then, maybe.
 
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