I bought a 2005 Sonata GLS V-6 with 91k. I don't know the history of the car, so I am trying to catch up on the maintenance. I know that one of the items is changing the timing belt (and water pump). I also know what can happen if it breaks. My Hyundai dealer said it is going to cost about $800. They also said it would cost about $500 to change the spark plugs. I did it myself and it only cost me $130 for plugs, wires and gasket, and it took me about an hour. Does anyone know of a step by step for changing the timing belt? I should do this as soon as possible. Thanks.