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I have a 2011 mazda 3i touring with about 34k miles, for about a month now I've been getting awful fuel economy, approximately 15mpg city. As far as my driving habits are concerned, I do hit a few stop lights on my way to work, but very rarely go over 2,500 rpm as the speed limit is only 45.

When I first noticed this I thought ok, I haven't cleaned my air filter (k&n filter) in awhile, so I did that. Got my oil changed (full synthetic), reverse image search email checker port checker made sure tire pressure was good and used sea foam fuel injector cleaner on my next fill up. Car is driving great, acceleration is great but my fuel economy is just straight terrible.

I'm trying to avoid having to replace the plugs/wires, to my knowledge mazda uses plugs rated for 120k and I'm not having any performance issues or start up/idling issues. Other than poor mpg

I have been using nothing but 87 Octane Sunoco fuel for at least the past 6 months and this is the first time I've had any problems. I live in PA, so it has been cold and some MPG drop off was expected, but I certainly did not expect to go from 26ish city down to 15. That's unacceptable.

When I had my tires rotated the mechanic told me they were a tad uneven, fronts were 8,7 backs were 6,6 but I can't see that having such a huge impact on the car.

I called Mazda and the tech told me that it's all computer controlled and there is nothing he could do if there wasn't a check engine light on.

Hopefully you guys can be more helpful than he was. Will provide any other information asked of me. Thanks guys
i drive like a maniac in it i still get 18 or so. I cant think of anything that would cause a mpg drop that significant.
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