I am finally getting to sort this car out. The car runs good under hard throttle but when I am coasting down a hill or running at light throttle the car surges or feels like it is missing. I checked the codes and there were none. I have tried three different computers. They all have the same problem with varying degrees. Also I have a new Mopar stage 2 in the car. It seem to be giving me more boost the more I drive it but I am only getting 11 to 12 psi max at this time with 10 miles on the computer. In the higher gears it shoots up to 10 but drops off to about 8 psi. I have a grainger valve but I want to wait until I have the miss corrected. I changed cap wires plugs and rotor no luck. Any ideas? O2 sensor?