Im having a problem with my 2001 Explorer, just changed the battery and when I take it out it for a drive it starts loosing power. New Altenator?

 

Check the output with a multi meter, it should be around 14 to 14.5 volts.

 

Did you have this issue before changing the battery? When you say "starts losing power" are you referring to engine power or electrical power?

-Rod

 

when you disconnect the battery, the computer looses memory and can resort to the factory settings. In a few days it will learn "your settings". Is this what your talking about, startup, idle, running.... or did it really "loose power"?