gud evening. I have got corolla 1990 equipped with 5AFHE engine.
Ist Issue is that its O2 sensor is present but has been left unwired with four wires hanging down. Its denso 4 wire sensor with 2 black,1 White and 1 Blue. As far as I have studied about its wires, BLACK wires are for Heater,BLUE is signal wire and White is Sensor ground. 1 Black wire is connected to +12V or +B while the other Black goes to HT pin of ECU. Blue connects to OX pin and and White gets to Sensor ground or E2. Plz do correct me if m wrong.
If this configuration is right then problem arises that how to locate pins on ECU,If somebody can show me the pin out diagram of this particular engine,It'd be highly appreciated.
2nd problem is that car is running without Diagnosis Box but its going good. Is it fine NOT TO have Diagnosis Box...??If NO,,what is the solution....?