Mine had that hesitation when accelerating from a stop, then it would also feel like it was going to die like it was running out of gas when cruising. I replaced the ICM, which fixed the hesitation and the running out of gas like symptom. But it left me stranded again and the car wouldn't start. I waited 5 minutes and the car started. I just replaced the coil, so hopefully that fixed the problem. But I'm betting it's the Opti that needs replacement. The previous owner had used parts that were low budget non oem.