i bought a 00 si about 9 months ago then later i realized i did'nt have a check engine light. i just put in a lamp and the light stays on. is there any possible way to check for codes to try to pin point the problem, or is there some other way to try to go about finding the problem

 

Yes, by the ECU there is a green plug. By the green plug you will find a blue plug looking thing with 2 wires going into it, but they go nowhere. You need to put something like a paperclip between the connectors to "short" it. Then, turn the key to the ignition position, and the check engine light will blink in a code. Long Blinks = 10, 20, 30, etc. Short blinks mean 1, 2, 3, etc.

So, 4 long blinks, and 5 short blinks would be code 45.

 

http://www.c-speedracing.com/faq/06.html

 

you guys are great. i went outside to check the codes and got a 41 code. on the link that i got there wasn't any mention of 00 civic so i hope these codes will apply

 

btw what is an oxygen sensor and do they go bad often

 

they dont go out often but they do go out randomly especially maybe when you are running too rich and clogs it.