i just check my MPG info. 12.3 MPG on it. how the hell is this it?

i put only but premium 93 on it.
i drive in city(65%) and highway(35%)
the oil hose is been fixed.( recall )

any ideas?

 

Are you going by the display? If so,try checking it manually.Also,when mine acts goofy once in a while I have a scanner that i use to reset the ecm.That helps a lot.

 

Well, there is something not right about that reading. Check it again in a few days. I have a 2007 model like yours. I average 24 highway and 19 city on the display. That is also close to what I have measured manually. If you have a large disparity in the readings, take it into Lexus.

 

Your air filter may need replaced if its been awhile.

 

Is someone taking out fuel in the middle of the night?

If not u must have a heavy foot but I think the readings are in error.
Fill the tank, write down the miles & drive till 1/4 tank is left then fill it up again. Take another milage reading & divide those total miles by the gallons added & that should give you a better idea of just what u are getting for MPG.

 

first (and this is very controversal on here) but i would put regular fuel in there (87 octane) the engine is designed to run on it, so you are just wasting money, i actually found that my milage went up when i switched to the lower grade. again this is very controversal.

second, since its winter (unless you drive down south) they put additives in the fuel to help cold starts, this directly affects mileage, so you might find in the coming weeks that your mileage goes up.

third, if you are running snow tires, that will worsen your mileage due to there inherent design. put summers on as soon as its safe in your area, for me, thats this week.

fourth, check tire pressure monthly, every 10 degrees change, affects tire pressure by 1 psi,

fifth, already said, check air filter

sixth, drive like an old lady

 

wr32, There is definitely a problem with something. I am getting an avg of 22.3-23.5 mpg mostly driving around town. Probably 70/30 city/highway. Something is sucking it up or pouring it out. Check for a tank leak, tire pressure, and filter as has been said.
I'm using 93 octane for 3 tanks but plan on reverting back to 87 here in GA as I cannot see any difference in mileage. Actually it seems to have a little more power with the 87 but that may just perceived in my mind only. Good luck.
Keep us posted please and Welcome.

 

Measurement error. It can not be that bad.

 

Mine went up 1 mpg going from Premium,to Mid Grade 89 oct.

 

Really? When I tried 87 in my 01 RX 300,it had no power at all. Even the transmission shifted different, (crappier) so I just ran Premium only in that one.

 

since i fill up, i have driven 4 times.
trip 1 25 mins ( city )
trip 2 45 mins ( city 25% , highway 75%)
trip 3 1 hour ( city 25% , highway 75%)
trip 4 1 hour ( city 25% , highway 75%)

total 3 hours. and i have about 55% lefted in the tank.

 

Ok,so what does this mean? I dont understand your reasoning here?

 

well i'm not sure if the sensor is right.

to put it in short.

i drove the car for 3 hours, aveg speed 30~40, and used up 45% of the tank.

the sensor still showing me 12.7 about 0.2 better.

 

I assume you started with a full tank and wrote down the mileage. If so, fill the tank and write down the mileage and the total gallons of fuel it took to fill the car. Divide the total milage driven by the amount of fuel it took to fill the tank. That will give you the actual MPG of your car since the first fill up.

I am sure it will be much higher than your Lexus display is showing. If so take it to Lexus. If it is the same as the display, something is wrong with the vehicle, so again, take it to Lexus

FYI, the amount of time you drive the vehicle is irrelevant to MPG.

 

^^Yeah, drop off your 300lbs girlfriend...J/K

In all seriousness.
Do you reset everything after fill-up?
Some times you can't rely on those readings. I usually do it the old fashion way of calculating as rainbird sugg.

One thing to that kills mpg on the info meter is idling for polonged period of time.
I hate it when my wife does this. She would idle for 20min+ just taking on her cell phone while she waits for me out of the gym.