Dr. Rx

I've tanked up my car twice since I've gotten it few days ago....so far about 250 miles on it. I taked up each time when it was at the halfmark and it only took 5.6-6 gallons on each fill. Manual states car has 15.9 gallon tank.....sound right or is the guage just not that accurate.

Loaded8

The guage isn't very accurate from my experience. That sounds about the same as mine... I've never emptied my tank all the way but I have put in over 14 gals, not over 15 yet... too careful for that so far.

Mikelikes2drive

my red light came on and i put in about 13.5 gallons in i wouldnt call the gas gauge very accurate

mrthundercleese

I usually use my driven milage as my "gague". Once i get 200mi+ i know its about time to look for a gas station soon. I usually fill between 200 - 250 and its never taken over 14gal. Mazda and these freak gagues... at least they got the tach right (9Ks w00t).

Irish_in_a_RX8

iTrader: (1)

I filled mine yesterday at the half mark ( perhaps just under ) at 7.9 gallons. Seems correct to me....almost.

Labop

God I wish I could get up to 200 miles..., I got to 193. But I also had to put in 13.9 gallons. I usually fill up about the time my light comes on, around 13.5 gallons each time.

Has anyone had any luck with using octane boosters? I'm just talking daily driving, not for high performance uses. I haven't gotten to that stage yet. I've had a couple of people in my shop (Navy term for office) use octane boosters, and they have reported getting a boost by 20-50 miles per tank.

kbull

My gas light comes on at just over 13 gallons (between 200 and 220 miles). And yes, the guage isn't very accurate. I always take note of my mileage at the first quarter mark, and it can be between 40 and 70 miles. Even then, I always get about the same mileage out of a tank.

Cycopath

i am kinda of curios to see what ours is going to be like. just under a 3/4 full and gone 65 miles

HeelnToe

Just for the record, I believe the manual says to not put any additives, boosters, cleaners, etc. in the 8.

But maybe all manufacturers say that... I dunno?

Either way, armchair theory says that unless you're experiencing knock, an octane booster won't have any effect.

SpearRX8

Gas gauge accuracy has gotten better with every reflash of the ECM. With the M, it is better close to 7.0 gals at mid point. I started with the K flash at 9 gals at mid point. Has this happened to anyone else?

silver1_rx8

ok I jsut got the M Flash and got 262 miles out of the first tank of gas, filled up 13.4 gallons and now I'm on my second tank...

picosrx8

I have the L flash and my needle hits half way around 150 miles. My low fuel light comes on around 280. I dont really pay attention to how much Im putting in (Im to busy crying at the price Im paying!)

mrthundercleese

^^^ sho do wish i could get that kind of mileage... I would be a happy camper then... as if i already wasn't.

IZoomZoomI

im usually at 110 by the half mark with the current m flash. whoa 280? wow thats way better mileage than what ive been getting! Are those all highway miles? i usually hit E at 220 sometimes at 210.

red_rx8_red_int

The m flash did change my guage reading. And it improved my mpg. But I don't know how much is attributable to the flash because that coincided with the gas stations switching from winter fuel to summer fuel.

Dr. Rx

Just tanked up for the third time at the half mark. First two times I calculated about 15mpg...this third time I got 19.3mpg. I probably should note that this was my 5th day driving the car, which is my first stick shift, but I've got the hang of it now. Plus I'm trying to be conservative with my shifting during the break in period. Currently at almost 400 miles... bough the car last Thursday on June 17th.