I just got my 96 3.6l mustang. It had a cel on when i got it. ( got it from my stepdad he didn't want it any more was gonna junk it.) that cel was for running to lean i forgot the code that was throwing. I replaced two vacuum hoses that where dry rotted. I cleared the code and it went away. I was driving the other day and the light came back on so i thought that it was for the same thing so i didnt bother to check it. Well i was driving the other night and it lost power but cam back right away. It did that a few more times. I hooked up my laptop and read the codes. Now it has a P0153( O2 Sensor Circuit Slow Response) and P0401 (Exhaust Gas Recirculation Flow Insufficient Detected). 200 thousand miles not sure how many because the odometer does not work. Would i need to replace O2 sensor? thanks for the help.