99 dodge intrepid car surges while driving

hello i got 99 dodge intrepid and had my motor rebuilt and now driving on the highway going 70 mph the car is surging bad and the tech. bounces around and check engian light comes on and reads p1391 and i replace both sensors and still surges any ideas please help

I have a 98 dodge intrepid and my did sounds like the same thing, however, my did it at stops. It would surge as though it was wanting to die, and then the rpm's would jump up to catch it before it dies. I took mine to a dodge dealer and they did a diagnostic check and it read the sensors too. I had to take it back 3 times as after the sensor was replaced it would still do it. Long story short it ended up being the ignition coil. One was bad and the car was missing, but it kept reading a sensor, go figure. Try this and see if it works, it did for me.