Description
Product Overview
The C 25 114/1 Engine Air Filter is precision-engineered for BMW vehicles equipped with the M52 and M54 inline-6 engines across the E36, E46, E39, and E85 chassis. These legendary BMW engines demand clean, unrestricted airflow to deliver their characteristic smooth power and responsive throttle. This direct-fit panel filter drops into the factory air box with zero modifications, providing OEM-equivalent filtration and airflow.
Key Features
-
Precision BMW Fit: Designed specifically for the E36, E46, and E39 air filter housings — exact dimensional match for the factory filter
-
Full Cross-Reference: Replaces C 25 114/1, 13721744869 (BMW OEM), and PC2233E
-
M52/M54 Engine Coverage: Fits 2.0L, 2.5L, 2.8L, and 3.0L versions of the M52 and M54 inline-6 engines
-
Pleated Cellulose Media: Provides the ideal balance of airflow and filtration efficiency for naturally aspirated and turbocharged (if equipped) BMW engines
-
Flexible Polyurethane Frame: Compression-fit seal eliminates the need for gaskets — the frame itself forms the seal against the air box
-
Maintains MAF Sensor Health: Proper filtration prevents dust and debris from contaminating the sensitive hot-film MAF sensor
Vehicle Compatibility
| Make |
Model |
Engine |
Chassis |
Years |
| BMW |
320i |
M52B20 / M54B22 (2.0L/2.2L I6) |
E36, E46 |
1992–2005 |
| BMW |
325i |
M52TUB25 / M54B25 (2.5L I6) |
E36, E46 |
2001–2005 |
| BMW |
528i |
M52B28 (2.8L I6) |
E39 |
1997–2000 |
| BMW |
M3 |
2.0L I4 (Euro) |
E36 |
1992–1999 |
| BMW |
Z4 3.0i |
M54B30 (3.0L I6) |
E85 |
2003–2006 |
Specifications
| Specification |
Value |
| Part Number |
C 25 114/1 |
| Cross References |
13721744869 (BMW OEM), PC2233E |
| Filter Type |
Panel Air Filter |
| Media Type |
Pleated Cellulose |
| Frame Material |
Flexible Polyurethane (Compression Seal) |
| Length |
Approx. 355mm |
| Width |
Approx. 178mm |
| Height |
Approx. 40mm |
| Service Interval |
30,000 miles or every 3rd oil change |
Installation Guide
- Open the hood — the air filter housing is located on the driver's side (left side) of the engine bay
- The housing lid is secured by metal spring clips — typically 4-5 clips around the perimeter
- Release all clips and lift the lid — on some models, you may need to disconnect the MAF sensor connector for full clearance
- Remove the old filter — note orientation (the rubber seal faces down into the lower housing half)
- Wipe out any debris from the bottom of the air box — leaves, bugs, or dust accumulation
- Inspect the intake boot between the air box and throttle body for cracks — a common failure on aging BMWs
- Install the new C 25 114/1 filter — seal side down, centered in the housing
- Replace the lid — ensure the alignment tabs engage properly before securing clips
- Reconnect MAF sensor if disconnected, then start engine and verify no check engine light
Frequently Asked Questions
Q: Does this fit my 2003 BMW 325i (E46)?
A: Yes. The C 25 114/1 is the correct filter for all E46 325i models (2001–2005) with the M54B25 engine. It drops right into the factory air box.
Q: What's the difference between C 25 114/1 and C 35 154/1?
A: The C 25 114/1 fits BMW E36/E46/E39 chassis, while the C 35 154/1 fits Audi A3/TT and VW Jetta/Golf/Beetle applications. They are completely different filter sizes and shapes — not interchangeable.
Q: Will a dirty air filter cause my BMW to run rough?
A: Yes. A severely restricted air filter creates a rich air-fuel mixture, causing rough idle, hesitation on acceleration, reduced fuel economy, and potentially triggering MAF sensor fault codes. On M54 engines, a dirty filter combined with a leaking intake boot is a common cause of lean codes (P0171/P0174).
Q: How often should I change the air filter on my E46?
A: BMW's official interval is every 30,000 miles under normal conditions. However, if you drive in dusty areas, heavy traffic with lots of idling, or notice reduced fuel economy, consider replacing at 15,000–20,000 miles. The filter is inexpensive and easy to access — erring on the side of more frequent replacement is never a bad decision.
Q: Can I clean and reuse this filter?
A: No. This is a disposable dry paper filter. Attempting to clean it with compressed air or water will damage the media and reduce filtration efficiency. Replace with a new filter at the recommended interval.
Related Products
Blog Resources
For BMW maintenance schedules, DIY repair guides, and M52/M54 engine tips, visit our BMW Enthusiast Maintenance Blog.
