Did you take the ISCV apart? I find that it's best to take it apart and soak the parts and give them a good clean and them put it back together again. There should be 4 parts in total, 2 springs (remember which one goes where), a nut , a metal collar and the washer.

Best to measure how far down the nut is on the threaded shaft before you dismantle as this can affect your idle level.

Works a treat on mine.........

Remember to give the runner o-ring some sillicone grease or WD before you put it back in, much easier to remove the next time.