Last Friday I filled up the 4Runner. Got 12 gallons, and 122 miles since last fill up. Yesterday, I filled it up again. Got 10 gallons, and 186 miles since last fill up. Same gas station. Same pump. Same mid grade gas. Same routes traveled. Same foot mashing the gas.

From what it seems, I have a hair less than half a tank now, and I think 125 miles.

What the hell?

 

i got 13 mpg on my latest tank.

got 17 the one before.

its all about how much you mash that pedal i guess.

 

forget to reset the trip odometer when you filled up the "first" time?

forget you sat idleing on the trail for like 4 hrs what weekend?

weather can have a LITTLE change in gass millage but usually not that much.

i can get 250-300 miles on my truck on ~17 gallons (5speed with hubs unlocked)

 

I always set the trip meter. I write downt he ODO too.

Havent wheeled in a while.

Havent towed the boat around in a while.

 

luckily your runner runs on water as well as gas, so maybe you should try pouring some evian into the tank?

 

That only works if I pour it intot he intake tube.

 

The only time my mpg deviates from tank-to-tank is when the pump either kicks off prematurely or if I overfill. Even then, my mpg will only be about 2-3 mpg difference, if that. I average my monthly fill-up's which smooths out that kind of deviation.

How are you calculating your mileage? I suggest subtracting your current odometer reading at fill-up from the previous fill-up odometer reading and dividing that by the # of gallons you put in the tank. I keep a daily planner in the glove box and log that at each fill-up. It's also a handy place to log your maintenance.

Good luck finding your "gremlin".

 

I reset the Trip meter every fill up. Then, when I fill it up next time, I take the miles traveled, and devide by the number of gallons i put in. Then Reset the trip meter agian.

By no means am I complaining about 18MPG, its just odd...

 

Its happened to me once too. I usually drive from lubbock to el paso, tx and the very last time i did I got 140 miles on my tank where I usually get about 340.

 

The thing is, I usually average about 12-13MPG calculated.

I did tap the air filter out on the ground. I doubt that would affect anything that much though.

 

Yeah, I do that in addition to using the other trip meter to track my oil change. The problem is that I was occasionally dumb enough to reset the trip meter so I stuck with keeping a log in the glovebox like I've been doing for about the last 20 years or more.

If that 10.x mpg reading was the only instance, I'd ignore it. You could have had a trip meter reset (duhhh) like I did or you logged the # of gallons wrong. Been there. Done that.

 

if you have stock size tires, chances are your mileage is off.

mine was off by 3-4 mph before i upgraded to 265/75 which made it "dead on balls" accurate.

 

I once got 59 miles on a full tank of gas.......

 

That 4LO...

 

Actually it was a during the Pritchett Canyon run in Moab last year, spent so much time idling around and not moving. Started off the morning with a full tank and when we got back my tank was empty....... Driving around in 4LL didn't help much either.......


Gangus2006, I wonder if that gas station has their pumps rigged????

 

It was most likely a case of not filling up all the way the previous tank. Sometimes the pump will kick off early if any fuel splashes up while filling. It happens on my 88 and I usually know how much it should take to fill so I force them to keep pumping. I thought I was getting some bad readings when I kept getting closer to 20 mpg but after 7+ tanks over 20 mpg I guess that's what I'm really getting. But if you average your 10 mpg tank and your 18 mpg tank together it puts you right back where you were. So I'd bet it wasn't filled up all the way.

 

I think it could also have to do with how many gallons were in your tank when you filled up. That could vary by up to 3 gallons if you don't let it go all the way to empty!

 

On my wife's 99 4runner 4wd we have been getting religiously 22-23 mpg with highway driving with the AC on full blast. City is around 17-18. No mods other than some decent ATs.

 

that sucks, maybe you should start drafting. i got 14 mpg on the highway trying to go 75 on the speedometer (actually about 85 cause of my tires), but when i drafted behind my friend in a ranger on the way home i got 23! i think i could get 25 if we kept it at about 60 and i was behind a tractor.

 

So thats the new way of describing tailgating.