I was going down the interstate last night putting some miles on the new motor and the Check Engine light came on. About 30 seconds later it went off. It did it a couple more times that night. I didn't think much of it and then it started to have trouble idleing. It would idle down and then cut off. I checked the TPS sensor and it was .585. I set it at .59 a week back b/c it would not idle and that fixed it until now. All of my sensors are plugged in and I have new o2's.

 

We can make thousands of guesses here, but the only way in my opinion to diagnose this kind of problem is to scan it and get the code causing the SES light.