This is Might be helpfull ?
I have a 2004 RX330. Filled the tank up the very min. the low fuel light came on. Held 16.2 gal. The book says it will hold 19.2. Three gallons left. The trip info. said there was only 17 miles cruising range left. This would not be right. At 20 MPG's X's 3 gal =60 miles left. Is my trip info wrong or is it suppose to be like this ?. Thanks for any comments.
Best Regards.........Bob

 

hey Bob,

We have the same situation as you did. The computer shows 14-17 mpg even though there is 3 gallons left is because to keep you safe from running low on fuel and to warn you ahead before you are too late to fuel up. Also, it best to fuel up at least 2-3 gallons before emptying since there are particles on the bottom of the tank, and if you keep runnin your car on low fuel, the engine will suffer from the grimes and will be clogged up with the particles from the bottom of the fuel tank as your fuel pump is sucking the remaining fuel. Just a reminder and notice. It is very common for automakers to calibrate the computer to show 14 or so mpg for this reason so that we should fill it up early as usual.

Dave