Replaced battery: does this alter Message Center mpg reading?

[kls490]

Good morning everyone,

I recently replaced the battery in my 2002 Explorer at an Advance Auto Parts store on 5/1/2015. After installing the battery, the employee said I should probably go and drive the vehicle for 15 miles or so. (This was supposedly to allow the on-board computer to "reset some things", etc, etc.) I frankly have no idea just what that means.

Issue Description: Prior to the battery replacement, the typical range for the Explorer's mpg shown in the dashboard Message Center would be between 13.6 - 15.2 mpg. Since the battery replacement, however, I've noticed on the 2 occasions I've driven the Explorer, the mpg shown dropped to 10.8 mpg (on the first trip out), and when I was out driving to the grocery store this morning, the mpg shown in the Message Center was now at 9.9 mpg.
(Fuel gauge is at 1/2 full, and the Message Center displays 216 miles until empty).

My question(s): Can someone enlighten me as to the reason for the sudden erratic drop in the gas mileage reading, after replacing the battery and only driving the vehicle two times since for approximately 20 miles?

(I do not notice any other strange behavior either).

Thank you for your time, review and any edification!

 

[drdoom]

That is like a reset, which you can do on the message center BTW. For instance if you reset and idle for a few minutes, you would have 0.6 mpg or so, until you drive for a ways. Normal.

 

[kls490]

Much obliged for that info, drdoom!

I was beginning to think I'd somehow managed to mess something up big time!

Cheers!

 

[drdoom]

You're welcome Pete, best wishes!