The bottom line here is he needs to use a new sensor in the pre-cat position. He needs to toss the hacked sensor/harness. If they switched the flat connector to a square connector on the pre-cat harness, I would replace it with the correct connector. Pigtails are available, see pigtail parts list, right hand column on Shoebox:

1993-1997 F-Body Part Number Collection

Then you need to make sure your SES light is working, and the previous owner didn’t disable it to sell you the car. I would also recommend you use an OBD-2 scanner to check for codes. You need to download a copy of the 1996 factory service manual - free courtesy of GaryDoug. It has everything you need to chase down codes, electrical problems, mechanical problems, etc.:

https://www.mediafire.com/?40mfgeoe4ctti

 

all 4 connectors are still there the 2 being used are flat plugs. I ordered the same sensors that were on the car ac delco AFS 97 and 98 Which are both square plug I also ordered the square to flat plug conversions from Michigan motorsports. Should I have done it a different way? Thanks for the link to the factory service manual. I appreciate both you guys time and efforts.

 

I guess I incorrectly ASSumed someone had moved a square connector after-cat sensor to the pre-cat position, and replaced the flat car harness connector with a square connector so the after-cat sensor could be plugged in. I explained that above in post #6, and repeated it in post #7. I guess I also mistakenly ASSumed you would have corrected what I wrote if that was the case.

I'll take another flyer at an assumption that you are replacing both pre-cat sensors. Why would they not both be the same part number? The Shoebox parts list shows the pre-cat sensors as AC Delco AFS75. Has that part # been superseded ? Or are you assuming that the existing part #’s are correct?

In any case, I’m so confused at this point that I think it’s time to drop out of this conversation.

 

I misunderstood what you were saying i acknowledged the fact that you were correct that they swapped the sensor from the rear to the front. I appreciate your time. Sorry for the confusion.