I have had my 2009 xB multi-LED display set to "Time" since I bought it.

However, with gas prices going through the roof, I decided to toggle the gauge through to its "MPG" function.

The readings displayed are rediculous - with the car maintaining a steady 35mph, the MPG numbers scroll rapidly (and randomly) from 4.0mpg through 90mpg. There seems to be no correlation between the amount I depress the accelerator and the reported MPG.

I called two Toyota/Scion dealers and both service reps I spoke to told me this is normal bevavior. I say this is B*** S***.

Can anyone help me determine if this is a ECU problem, or what?

Thanks, Marc

 

That's the instantaneous MPG display, it does that erratic scrolling normally to show the MPG at that instantaneous moment as you change speed or alter throttle input. If it's scrolling erratically at a constant speed, I'm not sure what's wrong. Could it be that you're cruising up or down a hill? If you're going down a hill with no throttle, it should be reading in the 90's since the fuel shuts off. FTR, if you continue to scroll through the options, the order of the displays should be: time, temperature, instantaneous MPG, average MPG, average speed, range or distance to empty, and engine time.

 

Thanks very very much Jnaval:

I had no idea there is a choice of two "MPG" readings. Tomorrow I'll experiment on the way to work.

Marc

(It's a pity I don't believe in instruction manuals. M)

 

Read it... you might learn something.

 

The instantaneous display can be useful if you're trying to find out what driving behavior has what impact on gas mileage. Of course, chances are you already have a pretty good notion on that relationship. For instance, down hill in neutral with your foot off the accelerator gives wondiferous numbers ! Whereas accelerator stomped up a hill in third gear takes the display in the other direction !

If you really want to see where your habits are leading you, monitor the average display. However, if you want to know what the real mpg numbers are, you have to calculate them by hand, fill-up to fill-up.