intermittment issue

[Century Weary]

Anyone out there know anything about 1999 Buick Century jerking when driving down the road speed approx 45-50 mph. It can be up hill or flat. It feels like it's not getting enough fuel. Fuel filter has been changed, CAM sensor replaced. One Mechanic mentioned tranny, another said no it's not. No codes come up. can it be fuel injector causing this?
HELP PLEASE
Terry

[Lefty22]

My bet based on your description of the problem would be that you have a problem with the torque converter clutch lock-up solenoid. Your car goes into overdrive at 45 - 50 mph. If the clutch locks up, then un-locks you feel the "shift" from fluid drive (unlocked) to direct drive (locked). You did not mention whether or not the problem goes away when you get faster 65mph and above.
Try this drive the car until it begins to act up. Slightly apply brake pressure. (not enough to activate the brakes, but enough to activat the brake lights) If the problem goes away, it is a problem with the torque converter lock up. If not, then it is something else.

[ventport]

If your car has individual coil packs you have a bad/weak one. With the car under load like going up a grade at low RPM in overdrive you will get a jerking or missing symptom.