my service engine soon light was on but i knew it would cuz my o2 sensors were disconnected for a couple days then today i put them back on and it still says service engine soon? did i mess up putting them back on or something? or do i have to bring it somewhere andtell the computer to turn it off?

 

Disconnect your battery for about 15 min. and then reconnect it and start your car up. Should make it go away..

 

negative terminal first buddy

 

You dont need to keep the battery disconected for 15 minutes.

Disconnect the negative terminal, and turn on the headlights for a few seconds. That will drain any power in the system.