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Discussion Starter #1
I installed a magnaflow xpipe with resonators to my already installed solo axlebacks and now I'm getting wierd mileage. Before the install the car was averaging about 21 mpg all the time. I checked the mileage the last two days on the way home from work on a trip of about 30 miles. In normal mode with dod kicking in I averaged 18.8 mpg. I tried it today in manual mode with same driving route and got 20.8. Any ideas what could cause the mileage to actually go up without dod?
 

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I don't think one or two trips is enough to gauge anything. There's so many subtle variations in traffic/temperature/gas quality/etc that it could vary quite a bit.

Your avg was 21 before... how many trips was that? compared to one at 18.8 with new exhaust, which I would wager was low because you were enjoying the sound of it. ;) The 20.8 in manual may be due to the trans not shifting as much because you were in manual, IE - downshifting when you goose it a little to get around someone, thus burning more fuel.
 

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Do what i did for about a month. Every fill up I wrote down mileage from the Odometer, the DIC for my economy, and the actual fuel input from the gas pump.

Found out I average just under 28 highway / 23 city. Figure in I also drive at most 3 over in the city, back roads, and 5-7 over on the interstate.

Sent from AutoGuide.com Free App
 

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Discussion Starter #4
Thanks for the info. I have been enjoying the sound so it could definately be part of it. I cleaned the MAF and TB today as well. The mileage just started dropping three days ago, not exactly sure why. I've had the solos for a couple of years and installed the x pipe last week. Time will tell i guess.
 
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