[lesabrefan]

9 months later, the same thing is still happening. I replaced coil packs with the same type from another car, did not fix the problem. While the engine is running, I unplug each spark plug wire and notice a change in the engine's performance, so I would assume each spark plug is working. The fuel pump and fuel filter have been replaced.
Here's what still happens, when the speed is about 30-40 and the car starts going up a little slope, the engine might sputter, if I release the gas for a second and press on the gas pedal again, everything is fine. If i'm on a highway and slowly bring the car up to 60-65-70, everything works perfectly fine. If I attempt to give it a little more gas and speed up a little faster the engine might sputter, once again, foot of gas and foot back on gas solves the problem. What else could it be?