2018–2024 BMW X3

2018-2024 BMW X3 — Engine Air Filter Replacement

By Tom Becker ✓ Certified Mechanic · Published Sep 21, 2026 · Updated Oct 14, 2026

🔧 Easy 20-30 minutes $35 DIY

Save $75 by doing it yourself! Shop cost: $110

Quick answer: Engine Air Filter Replacement on a 2018–2024 BMW X3 is rated Easy and takes about 20-30 minutes. You'll need 2 tools for this job, and parts cost about $35. This guide walks you through the full job step by step, including the mistakes to avoid.

Quick Video Tutorial

Parts You Need

Total Cost

$35.00

Part Name	Part Number	Price	Buy
Engine air filter for 2018-2024 BMW X3 (B46); verify engine, housing shape, and VIN fitment	—	$35.00	Amazon

About prices: shown prices are typical retail averages and change frequently; cheaper alternatives may be available. Confirm the current price before buying.

💡 Pro tip: Order all parts at once to save on shipping

Step-by-Step Instructions

Follow these steps carefully

Park, shut off, and open the hood

Park, engine off. Let the bay cool — the B46 turbo sits close to the airbox and stays hot. Open the hood. No covers come off: the G01 airbox is on the driver's side — a black box.

Remove the T25 Torx screws around the lid

The airbox lid is held by perimeter T25 Torx screws — not spring clips. Count the screws first. Set a magnetic tray nearby; the screws are small and easy to lose. Seat the T25 driver squarely and back them out.

Lift the lid and lift out the old filter

Lift the lid straight up. Note the old filter's orientation — which edge faces forward and how the gasket rests — before pulling it out. If anything resists, don't force it: the mass airflow sensor wiring runs through there.

Clean the lower box and check the new filter

Pull the old filter; compare with the new: same rectangle, same gasket edge, pleats facing the same direction. A due filter shows dark, packed pleats. Wipe the lower airbox with a damp cloth; clear grit around the sealing lip.

🔧 Mechanic's note — Ray Delgado

Downstream of this filter is the turbo. Dropped hardware in the intake opening goes straight into the compressor — I treat that opening like an open engine.

Seat the new filter and refit the lid

Drop the new filter in, matching the old orientation. Press it down; gasket must sit flat, no folds or gaps. Set the lid on squarely. Hand-start each T25 screw a few turns, then snug in a crisscross pattern.

🔧 Mechanic's note — Tom Becker

Plastic threads — hand-start every screw and snug them in a crisscross pattern. I cracked an airbox lid tab with a power driver once, and that was the last time.

Reconnect sensors and do a final check

Reconnect the mass airflow sensor connector if unplugged — push until the latch clicks, then tug to confirm. Confirm every T25 screw is back, none left in the tray. Check lid seam is even. Remove tools; close the hood.

Start up, listen, and note the interval

Start the engine and idle. Listen for whistling — a hiss means the lid isn't sealed. Watch for a check-engine light; if one appears, check the mass airflow connector. Follow service indicator, or replace when pleats are dark and packed.

All Done!

Test your repair before closing everything up. If something doesn't work right, double-check your steps.

⚠️ Common Mistakes to Avoid

• Overtightening the T25 screws on reassembly — the airbox is plastic and the threads strip easily, leaving a lid that never seals right again.
• Dropping one of the small Torx screws into the engine bay and leaving the lid held by one fewer screw than it needs — use a magnetic tray.
• Forgetting the MAF sensor connector if you unplugged it for slack — the X3 will run poorly and throw a check-engine light.
• Rushing the lid back on without checking the filter's gasket edge is lying flat — a pinched corner lets unfiltered air past the seal.
• Mixing up the order and trying to lift the lid before all the screws are out, which cracks the lid's screw tabs.

Tools You'll Need

T25 Torx driver or bit (airbox lid screws) Small magnetic parts tray or cup for the lid screws Damp microfiber cloth for wiping the airbox interior (optional)

⚠️ Safety First!

• Work with the engine off and the key away from the car — the electric cooling fan can start without warning.
• Let the engine bay cool before you start. The turbocharger and downpipe on the B46 sit close to the airbox and stay extremely hot after a drive.
• Keep loose screws, rags, and tools out of the intake path — a dropped screw past the airbox inlet is a one-way trip into the engine.
• Never run the engine with the airbox open and no filter installed. Unfiltered air and turbo suction are a bad combination on this engine.