I hooked my '01 5.4L F250 up to an advanced OBD II reader that showed me live data as it was running. So it showed that only one of my two O2 sensors were showing any voltage, so I replaced the sensors out and still no voltage. Another strange thing I noticed was that on the OBD status on the code reader it showed "OBD I" instead of OBD II. Any of this make sense to anyone or does anyone have any suggestions?

 

Your truck runs OBD1 software. It just happens to be running it on OBDII hardware.

 

Look under your hood on top of the radiator there should be a sticker that says if its obd 1 or 2 , My 2003 says obd 1 , it still has the same data port to plug into like a obd 2. I think that obd 1 has less things you can read with a scanner and also the o2 sensors are going to be different so your code reader will give you a funny reading. Hopefully someone more obd savoy will come along and give more insight.

 

Makes sense, thanks for the info guys. I thought maybe there was an electrical problem with my O2 sensor or the truck itself. Thanks again.

 

If youre truck is over 8600, (8800?) lbs gvw, it is emmisioned as a larger truck. You dont have the sensors that obdII scanner is looking for.