You're getting 20mpg with 100% city driving? I'm still calling bs if you are claiming that. However, mal's reasoning does make sense. I haven't seen anything that proves it but I obviously realize that the amount of air/fuel used is proportional to how hard you are accelerating.

With that said, my getting 14mpg has nothing to do with me not revving it out. It has to do with my driving consisting of 100% stop and go city driving and my lead foot. I enjoy romping on the car quite often, and when you are red line shifting it and chirping second once a day, you aren't going to get 17mpg city.

You can also shift at 3-4k and get great mileage, and I would be willing to bet the mileage you get when shifting at 3k-4k, is the same if not slightly better then shifting at 5k-6k. So don't go thinking you've just found some miracle cure for low MPG's....

When I first got my car I only got 21mpg on a 100% highway drive back home ( 300 mile trip ). I've not driven highway since then, but I had a post noting I was getting what seemed to be 5-6mpg lower then others, but was told it was probably due to breakin. I'll test this out sometime but as of yet I've not had the chance to run the car on the highway and see what its getting now. I don't know why my car would be any different, but there could be a sensor that is off or something.

 

Just a quick update:

The dealer of course said everything as completely normal.... Infiniti corporate wanted me to take it to another dealer, but when I called the other nearest dealer, they told me they only would look at it between 9-3 mon-fri, because I need to show them the issue I'm having. I'm 60 miles from them at the current site I'm working at, so I just can't go for the next few weeks.

BUT, I did get a call from the original dealer, and they're going to have an Infiniti engineer come in for something else on the 10th, and they'd like me to bring my car back in so he can look at it as well.

Hopefully they'll give me a loaner wed. evening and I'll be able to leave it there for them.

Keep ya posted ( what a great pun )!

 

hope all goes well

 

No sir. My daily commute is about 18 miles each way and mostly highway driving. I would have to estimate that my driving is probably about 70/30 highway, and very little of the non highway is of the bumper-to bumper variety taht wastes lots of gas. Hence the higher than average MPG.

However, only 21 MPG on a 300 mile highway trip doesn't sound right unless you were really hauling butt. I just went to Dallas and back on Tuesday. 574.4 miles round trip, 60.8 MPH average speed, 24.2 MPG. In a 6MT with cruise set at 75 MPH in the city and 79 MPH on the interstate. Very little traffic at 2 AM.

 

I get 20 MPG running 85-90mph on a 300 mile trip, so his #'s sound right to me.

What city is this!? I'm guessing you're still on the highway, inside city limits? Either that or you've got one of those nifty devices that can change stop lights

 

^^^^ LOL

Yeah that makes more sense about your MPG now. I'd say I averaged 80-85mph and was on the first tank of gas, I imagine its better now. So I didn't know it would make that big of a difference in MPG from 75mph to 85mph. So If i go steady 75mph I may see mid 20's for mpg? Thats nice, maybe I'll do that next time around. Thing is I pretty much never need to drive more then 5 miles in any direction where I live.

 

Correct. On Interstate 10 and 45 in Houston. Inside the city for certain, but highway driving.

And yes, I used to have one of those nifty devices but only used it once for fear of causing a crash that might hurt someone just to get somewhere 2 minutes faster. Plus it wasn't legal for me to have/use it. Got scared and gave it back.