Well, now that you know how to properly calculate fuel economy, then keep an eye on it. It's not a perfect system, but it's the closest we can get. I just read that the governor of CA was going to allow refineries to make winter blend 3 months early to offset the high fuel costs. That will surely reduce your fuel economy.
A tank every 2 weeks shouldn't really get into fuel separation, but you might want to try regular use of FI cleaner. One time treatments don't work. Treatments over time work. I always recommend Lucas fuel treatment, but I make sure that I point out that you don't purchase the little $4 5oz bottles. Always purchase at least a quart for $9 which has graduated marks on the side so you can gauge 4 oz treatments (the size needed for our tank), and then after that purchase a gallon container for $32. Use it to partially fill the old quart bottle for treatments. I regularly see a 3 mpg improvement in the van and the car using this. Since gasoline is over $3/gal, it's cost effective to use it just for the mpg bump. Now in your case, I don't know if it will increase your mileage that much, but you can check it out. I'd run a quart (8-4oz treatments) through there an monitor your mpg for each tank. If it's cost effective for you, then keep it up. If you ever notice your mpg dropping suddenly for one tank, then forgo the treatment on the next tank. Since you don't use all your gasoline up, some remains, and over time there can be a residual buildup. One tank without treatment fixes that.
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Originally Posted by the user formerly known as ZX3_Chick
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