Oldsmobile/Buick Repair: injectors?, compression pressure, buick century

Question
i have a 89 buick century it started to buck and jerk shake taking off. i put new spark plugs in it. and added a bottle of outlaw in it.it ran good for awhile but now its back bucking and hesitating,and shaking. is it injectors or fuel filter? no i did not change filter yet.car has 13000 miles on it. filter hasn't been changed since i bought it 5 years ago. i drove it from maine to arizona where i live now. any ideas would be helpful.are the injectors pressed in? thanks for your help ken

Answer
Hello Ken,
Actually, the injectors are only held in by the fuel rail. There is no compression pressure on the injectors. They just go into the intake stream on the back side of the intake valve.
I wouldn't remove them till after testing the fuel pressure.

Van