GT Newbie

My 2007 GT is now 3 weeks old and has about 350 miles, and even though I was expecting that it would use LESS gas the more it's broken in, I've found that the "average m.p.g." setting on the message center stays around 17 m.p.g. instead of about 19 m.p.g. like in the first 1 1/2 weeks...?
Is this normal folks...(that "could" be because I'm driving ..just.. a bit faster now- but I didn't think it would make THAT much difference cause I'm not beating it at ALL- just a little bit of a heavier foot).

Also, the message center "average m.p.g." setting was changing almost constantly when I first got it (almost every few seconds!), but now it stays exactly the same for minutes on end, and has only changed in the range of 16.9 - 17.2.
Does that sound normal too- or does the thing need to be re-calibrated for some reason...?
I remember that at first it was even changing while I ws stopped at a light- but it really takes a while now before the reading changes at all..........
puzzled...?

Zellanor

No worries, my 05 GT gets about the same as your 07, Take it out on the Hiway and run it at about 60mph, your mpg will jump dramaticly, On the Hiway I am about 26.5 to 27.5 mph's. There is no reason to recal anything. Good luck

FrostByte

Ya the heavier foot wil make a diff. try shifting @ 2k & watch milage go up, bet u cant do it for a whole tank!

hammeron

after the first 1000 miles, the mpg should be more consistent/accurate

swensicle

Please also understand that your mileage calculator is constantly averaging your mileage. If you reset it, it will jump around until it gets consistent numbers to base it self on. It will vary less and less as you increase the miles since your last reset. You should probably be resetting it every tank to get an accurate reading for that period. Also, colder weather and even slightly harder driving will make it vary more than you think. You'll get used to it.

GT Newbie

Thanks for the reassurance- but I also thought it was weird that the "average m.p.g." readout was changing almost every 10 seconds or so the first 2 weeks I had it, and is now basically staying the same for up to 10 minutes (not even going down at stoplights anymore)....?

When I get a chance I'll take her for a spin on the highway and see what happens (if I can manage to control myself and stick to the 65 mph speed limit that is...;-)

GT Newbie

Thanks swensicle- that does sound to me like it makes sense!
I reset the trip odometer every time I fill 'er up- does that automatically reset the average m.p.g. indicator too...?
I suppose 17 average really isn't too bad considering I'm driving about 90% "city" traffic at the moment.........

GT Newbie

Yeah, I pretty much babied it and stuck to 2K r.p.m. for the first 150 miles, so I guess that WAS enough to make that 2 m.p.g. diference.......

Rt1Rebel

I'm seeing the same thing. When I first got her, I was getting 21 on the computer and closer to 22 in reality, and I was driving very gently (most of the time) until I got the feel of it.

I was puzzled that it had dropped to slightly less than 20, both on the computer and in reality for the last few tanks, so for a test, I restrained myself as much as I could when accelerating, like I did at first, and my mileage popped back up to 21.

And as has been mentioned, everytime you refill, make sure you reset the MPG, or you will be adding on to the previous averages.

GT Newbie

Thanks rt1rebel- I think that probably explains the difference in mileage (a simple case of creeping Lead Foot Symdrome...;-)