The engine air filter is in the engine bay, inside a rectangular airbox on the passenger side, while the cabin air filter sits behind the glovebox in the cabin. Here’s how to locate and replace both if needed.
Engine air filter location
The engine air filter is housed in a large rectangular plastic box on the passenger side of the engine bay. A breather hose and a plastic intake snorkel connect the box to the front of the car, feeding air from the grille area into the engine. The lid is held on by clips or screws, depending on the exact trim.
To locate and replace the engine air filter, follow these steps:
- Park on a flat surface, apply the parking brake, and open the hood. Locate the rectangular airbox on the passenger side of the engine bay.
- Release or remove the clips/screws securing the airbox lid, then lift the lid to expose the filter.
- Remove the old filter and inspect the housing for any debris or moisture.
- Insert a new filter with the correct orientation (the part typically has an arrow or notch direction). Ensure it sits evenly in the housing.
- Reinstall the airbox lid and secure all clips or screws firmly.
- Close the hood and start the engine to verify smooth operation and no unfiltered air leaks around the housing.
Concluding note: After replacing, ensure the seal around the airbox is airtight to maintain proper engine performance and fuel efficiency.
Model variations and accessibility
While the general location is the passenger-side airbox in most 2011 328i models (E90), some configurations may place minor components slightly differently. The basic access method—unclipping the lid, replacing the filter, and resealing—remains the same.
Cabin air filter location
The cabin air filter is located behind the glovebox in the dashboard. Access requires lowering or removing the glovebox to reach the filter housing, which is usually clipped or screwed in place.
To replace the cabin air filter, follow these steps:
- With the glovebox open, release the limiting stops or detach the glovebox damper to allow the box to drop down more easily.
- Locate and remove the cabin filter housing cover, which is typically held by clips or a small screw.
- Take out the old cabin filter and note the correct orientation (the filter usually has an arrow indicating airflow direction).
- Insert the new filter with the correct orientation, ensuring it sits flat in the housing.
- Reattach the housing cover and secure the glovebox back in place.
- Close the glovebox and test the climate control to ensure proper airflow and that there are no unusual noises.
Concluding note: Replacing the cabin filter can improve HVAC performance and keep interior air cleaner, especially in dusty environments. Consider replacing roughly every 15,000–30,000 miles, or per your vehicle’s maintenance schedule.
Summary
For a 2011 BMW 328i, the engine air filter sits in the passenger-side airbox in the engine bay, while the cabin air filter is behind the glovebox in the dashboard. Both replacements are straightforward with basic hand tools and careful reassembly, helping maintain engine performance and interior air quality.
Where is the air filter in a BMW 328i?
So here's our N20 engine bay. And our air filter is going to be below here so yeah a little pro tip for you guys always get yourself some rubber gloves. That are disposable.
How much is a 2011 BMW 328i worth today?
2011 BMW 3 Series 328i Sedan 4D Annual Depreciation
| Year | Vehicle Depreciation* | Resale Value |
|---|---|---|
| 2023 | $503 | $6,930 |
| 2024 | $853 | $6,077 |
| 2025 | $999 | $5,078 |
| Now | $153 | $4,925 |
Does a cabin air filter help with allergies?
Cabin air filters also help to reduce the amount of those allergens that can get into your vehicle. Pollen, dust and other allergens can build up in your filter during heavy pollen season, so you may need to change it sooner.
How much does it cost to replace a cabin air filter on a BMW 328i?
between $140 and $209
The average cost for a BMW 328i Cabin Air Filter Replacement is between $140 and $209. Labor costs are estimated between $74 and $109 while parts are priced between $66 and $99. This range does not include taxes and fees, and does not factor in your unique location. Related repairs may also be needed.