okay i looked at the articles for the check engine codes and i can figure how to read the led or whatever but what plug is it? is the plug connected to the ecu itself? I have a 93 civic si with jdm b16a with p30 ecu obd1 of course. It is the middle plug out of the three that connect to the ecu or is it by the ecu? I tried to look for a blue colored plug like the 97b integras but didn't find any, please help. 
