Hey everyone,
So recently I filled my tank at a conoco station. I drove around normally and expected my nromal average to show up at 45 mpg (yeah right under 46, if I didn't speed I'd hit 50mpg city easy). However, I'm notcing some strange stuff on this gas type. First of all, my mileage on this tank is just fighting for 42 and often drops dangerosuly close to 40mpg. Don't get me wrong, I'm happy about getting 40mpg but only compared to a non-hybrid car. Also, my tank is already about half empty with only about 220 miles on it. Any one else experiance somthing similar? (Also when I tried mid-grade gas once to see if there would be a performance difference, it seemed to drain my tank faster, but I also got that gas at a conoco station!) What company gas seems to get the best mileage on a tank?

I don't think there has ever been a definitive answer to this question.

However, WINTER BLEND gasoline is less fuel efficient because of additives (I think that's the reason) so part of your answer could be that you might have gotten your first tank of Winter Blend.

Actually, unlikely as it seems, I tend to notice better mileage after filling up at a particular station... it's the same brand as the other station I commonly use, but they're in different cities (at the other end of my 80 mile commute). I tend to doubt there's that much difference in gasoline, especially when they're both 66 stations, but the difference was conspicuous. I imagine the other difference may be that the prevailing winds and such make it look better at first because I am driving the other direction a the beginning of the tank... but when I look back through the log book, the tanks from the one station seem to do better than the tanks from the other. Anyone think there's any truth to this or is it perception and or/conicidence?

Zimbop, for you it might be more coincidence just cause as you said 2 different stations. Maybe the terrain is a factor? I only noticed because my driving habits have stayed the same, the weather has actully been better than what it has been around here (I've only had the car for about 3000 miles now) and I've been driving the same places and thus the same terrain to and from work. With my first tank of Conoco gas, I was actually about to hit a highway from Fort Collins to colorado springs which is more of a downslope. However, I got better mileage on the way up to Fort Collins, with more traffic than I did going down (It was also the first time I filled the tank).

Well you could have gotten a tank of gas with a high water content in it.

Think about it, gas in made in many refineries from oil that comes from all over the world. After refining they send it up pipelines in batches as I understand it, hightest, mid grade, regular. We hear of some at stations with water in it. Age of gas affects it too. I once bought a lawn mower at a garage sale and it would not start, but had gas in tank. After awhile of tinkering with it, I smelled the gas and it did not smell right. Poured it out put new in and it cranked right up. The small amount of old gas was out by curb on street. Put a match to it from a distance and would hardly burn...old gas I suppose. So there has to be many factors and you may not get the same quality at the same station the next time you are there. I suspect that they manipulate the pump accuracy at some stations too, but hard to prove. I feel like I have noticed differences in tanks from different stations too. The HCH just shows it more than a regular car will. Not much we can do about it!

well that does suck, but I'm glad to see that I'm not just imagining this and it could actually be something up with the gas. I just won't buy from those stations anymore!

I had been told to never buy gas at a station that was getting a deleivery (i.e tanker truck unloading) as the gas being deleivered would "stir up" the fuel already in the tank, and any any water and sediment that settled out could get dispensed. Never thought much about it, as my luck never had me at a station at the same time a deleivery was taking place, but it may very well explain some of the problems reported here.

Larry
'06 Magnetic Pearl HCH #7264

Top Tier Gasonline, as defined by BMW, General Motors, Honda, and Toyota

http://www.toptiergas.com/index.html

I must admint this gave me a chuckle. What a fabulous test for gas quality.