Ok I got the O2 sensor put back in the exhaust system. And i drove it around the O2 sensor is working got rid of the engine running rich but at the slower speeds the truck still wants to jump around a little and back fires still any suggestions on how to solve that problem.

 

Did you have the fuel sync set?

 

What do you mean by the fuel sync set?

 

Fuel sync is the relationship between ignition timing, and injector timing. Whenever the distributor is disturbed, (like, when replacing the engine....) it needs to be reset. You can't just set it by ear...... need a scanner that'll actually read fuel sync. If a shop installed your motor, ask them about it.