Okay, so I've got a 1991 Lumina Van, ~140,00 miles on it. I recently noticed an intermittent clicking sound coming from the engine, accompanied by minor roughness of the engine. Now the clicking is constant, and the engine is starting to stutter occasionally when given gas, but is fine when idling. I'm not sure if the two issues are connected but they started at approximately the same time. The stuttering can vary from minor, just a small hiccup, to a severe jerking. It only starts stuttering after the vehicle has warmed up, approximately 10 minutes of driving.

Any help or suggestions would be greatly appreciated.