1.4/1.7/2.0?
It's more than likely going to be a fueling problem, because if you changed the plugs and it was better temporarily i pressume they were sooted up or "wet" from over fueling hence giving a weak spark.
Have a look in the engine section at the sticky at the top, "poor running"
Running poorly
Re: Running poorly
89 3dr 340DL in Battleship grey with Ultralights and Williams power
Whats the matter with the car i'm driving can't you tell that it's out of style?
Whats the matter with the car i'm driving can't you tell that it's out of style?