1. Open the hood of your Sienna.
2. Locate the air filter housing. It is a black plastic box located on the driver's side of the engine compartment, near the top of the engine.
3. Unlatch the air filter housing. There are two latches on the side of the housing. Press down on the latches and lift up on the cover.
4. Remove the old air filter. Pull the old air filter straight up and out of the housing.
5. Inspect the old air filter. If it is dirty or damaged, replace it with a new one.
6. Insert the new air filter. Make sure the new air filter is seated properly in the housing.
7. Close the air filter housing. Press down on the cover until the latches click into place.
8. Close the hood of your Sienna.
That's it! You have now successfully replaced the air filter on your 2004 Toyota Sienna.
