The year is 88’. What i've done so far is check the potentiometer, the TPS switch and today i’ll check the EHA valve today. Also i found that static duty cycle at 50% means bad O2 sensor so i got a new one and now the duty cycle is stuck at 93%. I got mixed information on what it means but in most places i’ve read it means no connection with the EHA valve or bad valve(very unlikely). If you have any other ideas I’m all ears

Thanks