part
verifiedCabin microfilter element
The current MANN application catalogue maps the 8430 filter family to the E90/E91 320i N43 production range.
RELEASED MAINTENANCE GUIDE
E91 cabin microfilter replacement
BMW 3 Series Touring · E91 LCI · 320i · N43B20
All six steps are released with current component-manufacturer fitment and installation evidence, including a six-fastener removal checkpoint. Confirm your exact vehicle and replacement part before starting.
FASTENER PLAN
Know what must be replaced before you start
WrenchGuide tracks fastener material, reuse policy and tightening specification separately. A torque-plus-angle instruction does not automatically mean a fastener is torque-to-yield or single-use; the replacement rule must be verified independently.
0mapped fasteners
No verified fastener map is published for this procedure yet.
WrenchGuide will not guess whether a bolt is aluminium, reusable, torque-to-yield or replace-after-removal, and it will not invent a torque value. Exact vehicle, engine, transmission and drivetrain applicability can change the answer.
Replacement rule and tightening method are different facts.WrenchGuide only labels a fastener replace-after-removal, aluminium or torque-to-yield when the applicable evidence supports that exact statement. Torque + angle is shown as a tightening method, not used as proof of torque-to-yield by itself.
BEFORE YOU START
Parts, tools & supplies
WrenchGuide builds this list from the repair itself. Mandatory items only become hard requirements after their need has verified provenance.
0%0/2 required items confirmed
Required before start2
tool
verified8 mm socket and hand ratchet for the six microfilter-housing fasteners
The MANN installation sheet maps six housing fasteners and an 8 mm driver; AUTODOC independently corroborates the count and socket size.
Recommended1
tool
corroboratedClean vacuum crevice tool or soft brush
Loose leaves and dry debris should be removed before the housing is closed.
Fitment and approval are separate checks.An OEM/reference number narrows a part search and an oil viscosity narrows a fluid search, but neither replaces the verified vehicle fitment or manufacturer approval. Production date, VIN, engine/transmission, installed hardware and current product data can still matter.
Confirm the vehicle and replacement filter
DO THIS~3 min
- Confirm the active vehicle is an E91 and check the production/build information where available.
- Confirm the replacement is from the CU/CUK/FP 8430 family or has a current manufacturer cross-reference for the same vehicle.
- Before opening the housing, check that the new element is undamaged and note any airflow or installation-direction marking.
No tools required for this step.
Cabin microfilter element × 1replace with new · MANN lists several BMW OE cross-references for this filter family. Do not select a BMW OE number without VIN/build confirmation.
SOURCES & PROVENANCE2 linked
MANN-FILTER CUK 8430 application catalogue
MANN+HUMMEL · BMW 320i E90/E91/E92/E93 · N43 B20A · 09/2006–12/2013; dimensions 810 × 123 × 20 mm · accessed 2026-08-12
CU/CUK/FP 8430 mounting instruction
MANN+HUMMEL · Document 26 210 75 593 / AE0 / 06.14 · BMW · indicated time 15 minutes · accessed 2026-08-12
Progress saved locally on this device.
MY WORKSHOP JOURNAL
Remember how your car came apart.
Attach private notes and your own teardown photos to the exact procedure step. They stay on this device in the current local-first beta.
NOTESAuto-saved locally
Confirm the vehicle and replacement filter
MY PHOTOS0 / 6
Image only · up to 12 MB each
No personal photos for this step yet.
Take a quick photo before disconnecting or removing something you may need to identify during reassembly.