In short, the engine air filter in most Nissan Altima models sits inside a rectangular plastic air box in the engine compartment on the passenger side, connected to the intake hose that leads to the throttle body.
Across generations, the air box generally remains in roughly the same area—the passenger side of the engine bay toward the front or firewall. Access typically involves releasing clips or screws, lifting the lid, and removing the filter for inspection or replacement. This guide outlines where to look and how to replace it across common Altima generations.
Where to locate the air filter box by model year
Use the following as a quick locator guide. The air box is generally found on the passenger side of the engine bay, near the fender or firewall, and is connected to the intake tube.
- 2007–2012 Altima (2.5L and 3.5L): Rectangular plastic air box on the passenger side of the engine bay, with the intake hose running to the throttle body. Clips or screws hold the lid in place.
- 2013–2018 Altima: Similar layout; box sits on the passenger side, often toward the front or middle of the engine bay, with a large air hose linking to the throttle body and a removable lid secured by clips or fasteners.
- 2019–present Altima: Still generally on the passenger side, though some trims move components such as the battery. Access remains via the clip/screw-fastened lid; the filter is replaced by removing the lid and sliding the filter out.
Regardless of generation, if you’re unsure, consult the owner’s manual or a repair guide for your exact VIN, since there can be minor variations by engine and trim.
How to check and replace the air filter
Follow these steps to inspect and replace the air filter safely and correctly. A visual check can help you decide if replacement is due; most drivers replace every 12,000–15,000 miles under normal conditions, more often in dusty areas.
- Turn off the engine and open the hood. Locate the air box on the passenger side of the engine bay where the intake hose connects to the throttle body.
- Unclip or undo the fasteners securing the air box lid. Some models use simple metal clips, others use screws or bolts; keep track of hardware.
- Lift the lid and carefully remove the old air filter, noting its orientation (the dirtier side usually faces down or toward the box’s bottom in most designs).
- Inspect the filter. If it is dark, stained, or visibly clogged with dust and debris, it should be replaced; if it is still light and flexible, you may be able to clean it briefly (note: most OEM filters are not reusable and should be replaced).
- Insert a new, properly oriented air filter into the housing. Make sure it sits evenly and that the sealing edge sits flush with the box.
- Reattach the air box lid and secure fasteners or clips. Start the engine and listen for any hissing or unsealed gaps, then reset your maintenance reminder if applicable.
Maintaining the air filter helps engine efficiency and fuel economy, and a blocked filter can trigger reduced performance and higher fuel consumption.
Summary
In most Nissan Altima models, the air filter lives inside a rectangular plastic box in the engine bay on the passenger side, connected to the intake duct. Locating and replacing it is a straightforward maintenance task that you can do with basic tools and without special equipment. Always consult your owner's manual for model-specific details, and replace the filter at the interval recommended for your driving conditions.