sorry i duno how the tappet spells... my car got some prob... when i let go my accelerator the car just slow down a lot.... like the engine not smooth oledi... my fren told me to get my tappet serviced... he said those mechs use something like a knife to clean it i suppose.. how much is it? normal workshop can do it? cos i wana change my engine oil this weds... using castrol gtx i think... any other better brand beyond the price of castrol?