I have what may seem like a dumb question but I don't know the answer so plz just help me out. (yes I've searched for answers already) I have a 1990 si still running stock and the check engine light is coming on. I have tried to read the ECU. I think it is reading just a 1 but I'm not sure how long a pause there should be between flashes in order to read it. It started when I tried to replace my O2 sensor and found out the current one is siezed in place. So I recconnected it. That is when my check engine light started coming on after around 15-20 minutes of driving. If someone could help me understand what the timing is on reading my ECU I would be gratefull.