1. Open the hood of your Nissan Altima.
2. Locate the air filter housing, which is usually located near the top of the engine compartment. It's a black box located on the right front of the engine bay.
3. Unlatch the air filter housing cover. Depress the locking tabs that connect the lid to the base and lift the cover up and set aside.
4. Remove the old air filter from the housing.
5. Inspect the air filter for dirt and debris. If the filter is dirty, it's time to replace it.
6. Insert the new air filter into the housing, making sure that it's properly seated.
7. Reattach the air filter housing cover. Push down on the cover to lock it in place.
8. Close the hood of your Nissan Altima.
Be sure to replace the air filter according to the recommended maintenance schedule for your Nissan Altima. This will help to ensure that your engine is getting the clean air it needs to operate properly.