[SentraSE-R]

I have a problem. 8 of my last 10 tanks have been under 50 mpg, and those 10 tanks average 2.6 mpg worse than average. They've brought my average mpg down from 49.6 to 49.3 mpg.

I changed the air filter and checked spark plug gaps. New tires may contribute to the low mileage, and I was fighting headwinds on several of the recent tanks, but the trend is worrisome. I'm gong to replace the front O2 sensor to see if it helps.

Suggestions?

Date..........mi...gal......mpg
2013-01-29 268.7 6.05 44.41322314
2013-01-30 364.5 7.13 51.12201964
2013-04-13 460.6 9.42 48.89596603
2013-05-02 422.2 8.771 48.13590241
2013-05-02 321.2 7.464 43.03322615
2013-05-03 240.6 5.156 46.66408068
2013-05-06 328.5 7.3 45
2013-05-06 119.7 2.837 42.19245682
2013-05-07 356.3 6.913 51.54057573
2013-05-07 341.3 7.431 45.92921545
0
............... 3223.6 68.472 47.07909803
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