o2 censor
The engine warning light for emissions might come on in a Toyota Celica if the Oxygen Sensors are bad. It might also come on if the catalytic converter is not working properly or is plugged.
Could you please narrow down what lightbulb?
The fender must be removed so the light will slip out
if its like a "86" you just pull back on the light switch i
Use your test light to make sure there is power coming through the fuse and through the switch. If so, there's a broken connection somewhere. Also check the ground at the taillight sockets. A bad ground can drive you absolutely buggers.
http://www.toyotacelicaonline.com/airbagtool.htm or take it to dealer
If you press the brake down and the light comes on, a brake light is out. If it is on with your lights on, it means a tail light is out. The warning references are on page 47 (89 celica) manual...
It sometimes is refered to as a 'pigtail' or socket 'harmess'.
It's most likely your alternator going out, or something wrong with the charging system.....
Over drive
It is most likely your oil pressure light if it is red