my console is 4mpg off from had calculated. reads 18-19 mpg and i only get 14.3 every time

 

Mine lies like a dog!

2-4mpg high vs. hand calc. And depending on driving city/fwy/empty/loaded.

Tony

 

hand calc. I get 19mpg... the lie-o-meter consistently shows 23mpg

 

This weekend my overhead said 13.6, but hand calc. was really 10.1. So about 3-4 mpg off.

 

It's usually right with compass direction and temperature. Consistently off by 4mpg as far as mileage though.

 

I only use the overhead mph reading when I show it to my brother in law and rag on him about his Chevy. Other than that all it does is make you feel good. Has nothing to do with what's true!!!!!
Jay

 

Mine is consistently off 4mpg also. I average about 16mpg hand calculated.

 

Wow, seems pretty consistent based on these replies. Mine reads between 22 - 23 mpg, and I hand calc between 18 and 19 mpg, so I'm about 4 mpg off as well.

 

2 or 3 times ive checked mine it was around 1-2mpg off. you gotta reset that thing often. like if your pulling then daily driving. it will stay low after pulling even though your getting better.

 

I reset after every fill, and its been reading consistently 10% low for me. 18mpg is displayed when hand calculated to be about 20 mpg.

How accurate are your speedo/trip meters? Have you compared the readings to something like a GPS.

 

Overhead computer actually indicates fuel economy??????

j/k.......Mine is 2-3mpg off so I don't even look at it, except for temperature every once in a while.

MikeyB

 

I always hand calculate and avg around 19 to 20 mpg with mostly FW driving. I try to keep the tack around 1700/1800 rpm @ 65mph. The overhead consistently reads about 3 or 4 mpg better (23 - 24).

 

Mine's not close either, it's way off when I run Craszy Larry which according to the overhead gives me the best mileage.
I get me best economy running stock though.

 

Mines right on every time I hand calculate. You gotta leave it be. The longer it goes without a reset, the closer it will be. It measures mpg since last reset. The LAST RESET is what's getting you. If you hand calculate since last fillup, it will always be different, since your calculating something different.

 

mine is off 1 to 3mpg off