1) Is the first generation 4age fitted in ae82 rollas supposed to have a diagnoisis port!? I dont know whether they are meant to have one or somebody that previously owned my car removed it! I noticed my mates ae92 fxgt has one The diagnosis port is usally mounted on the strut tower and has another module mounted on the firewall. The reason being is i need to do a self-diagnois on my engine as it aint running rite but my car doesn't appear to have one, things then get pretty tricky!!!
2) Oxygen sensors - these sensors are supposed to monitor the amount of oxygen content in the exhaust gases and adjust the fuel/air mixture accordingly. How important are these sensors cuz not all first gen 4age's such as mine have them, why is that? Could that explain why my car still is running too rich???