I swapped out the fuel pump and it has been running fine until this past weekend. Fuel pressure is fine, swapped out the diaphragm in the FPR, still runs like dirt. We were going to adjust the timing but.... after we unplugged the EST, the car ran fine. Took it out for a drive and it didnt stall at any lights / stop signs or pulling in the driveway. Would this conclude that the EST is bad or the ESC? However, the car felt like it was underload after we did this. When the EST was connected again, it would start and then stall within a matter of minutes.

 

Anybody? Knock sensor unplugged, runs fine... Why is this? Is it bad?