Just repaced my battery in my 02 jeep wrangler.It cranks good but now won't start.Any ideas

check for spark
check for fuel

before was it hard to start(when the batt was adequate) then the batt went bad & you replaced it & now it will crank but no start? OR did it start good then the batt went bad, replace it & now good crank but no start?.

Before the battery was ok,just getting old so i thought i'd put a new one in to keep from having trouble.Looks like i created trouble.It cranks fine but won't start.I called a mech friend, he said he'd run into that and to turn the on for about 5 min to reset,if it won't start then he said it would have to go to the dealer to get reset.

the computer has to re-set itself. Somethimes it will take a few attemps, then when it does fire it will run like doo doo until you drive it around some.