Has your mpg gone up after few months? mine has

[Int3grity]

By how much has your mpg rate has gone up after owning the car for a few months? My current mileage is 6890 and now I am getting 280-320 on a full tank of gas. That is driving the car on full auto, I got tired of driving in manual I would often forget I was in manual mode LOL.

I recall at 1st getting 240 max on a full tank.

By the way a customer at the dealership was telling me they began using regular gas and have not experience any performance issues. Any word on this?

 

[motopilot]

We alwasy seem to get over 300 a tank and that is with 80% highway. It seems the heavy foor driving around town is where you loose the milage. We have been usually getting 21mpg a tank on preminum. Don't know about the regualr though, especailly on a turbo.

 

[SuperStretch18]

My mileage started out terrible, but has since gotten much better! I have about 4K miles at the moment and getting about the same range as you; about 280-320 with mixed highway/city driving. In Florida, so the A/C is always on too!

Regarding the premium gas question; I wouldn't take my chances. The difference in cost is not that high (.20 x 15 gallons = @ $3/fill-up) to warrant messing with it. I would be more worried about detonation with lower octane fuel than anything. I have driven in my father's porsche when he accidentally filled up on regular and it is not a pretty sight...

 

[Gasological]

If you'd like to try it, go down a grade, but only get a couple gallons on an empty tank. If you don't notice anything going wrong, then you could probably get away with using medium. Try again for low grade if you'd like to chance it. The moment you notice ANYTHING funny, fill up with premium to dilute the low octane fuel and protect your motor. Personally, I wouldn't do it, but if you're going to try to cut costs, for christ's sake do it safely, slowly, and in small increments.


Also, the increase in milage might be due to summer blend fuels that are less oxygenated (I think.....).

 

[Mazda3]

I have 19,000(12,000 miles) Km's on mine now. I'm getting 18.5 MPG consistently with 100% city driving. Defintely bearable for this type of vehicle.

 

[Rick's CX-7]

I have filled up with 100% 87 Octane and never noticed a problem. The owners manual states transmission shifting will be affected.....I couldn't tell a difference on the various times I tried 87. No noticeable knocking or pinging either.....even when floored for extended periods.

I do always fill with 93, since those trial runs.

 

[erhayes]

I wonder why some manufactures engines need so much running time to achieve optimum performance? Neither my Saab's, Volvo's or Subaru's needed more that a couple of tanks of gas to stabilize the mileage. Maybe some engines are better fitted (assembly tolerances and part finishes) than others. Whill be interesting to see what happens to my CX7 as I only have 100 miles or so on it.

 

[Killer]

Engine breaks in things get looser. Pretty simple really.

 

[fatlard]

I been getting 23-25 miles per gallon consistently.

2,200 miles so far.

I drive it very gingerly and mostly on highway.