HOw to get into engine to change spug pluggs and leads for Toyota estima 1993

The best thing to do is to purchase a Haynes manual for the Toyota Previa. But to access the spark plug wires and spark plugs you will need to remove the passenger front seat. This requires taking out four bolts on the four corners of the seat. After the seat is removed you need to remove the outside seat support and the jack and jack handle that is located under the seat. Next remove the bolt from the seat belt/shoulder harness. Romove the screws from the side of the carpet keeper strip along the bottom of the door. carefully, using a flat blade screwdriver, pry the plastic carpet strip up carefully disengaging it from the rear strip. Unhook the carpet from the edge of the doorway. Pull the carpet back enough to expose the bolts holding the cover over the engine. Remove all the bolts holding the cover over the engine. This will expose the engine head. remove the three bots holding the black plastic cover over the spark plug wires. This wires can be removed allowing access to the plugs. Be aware these engines use only platinum tipped spark plugs. Good Luck