BMW 3 Series Touring · E91 LCI · 320i · N43B20 · Manual
A novice-oriented, evidence-linked engine-oil and filter journey for the BMW E91 LCI 320i with N43B20, from vehicle confirmation and safe access through leak checks, electronic level validation, CBS handling, disposal and service history.
14/14 steps released · about 150 minutes for a prepared first-time owner · stop gates remain mandatory.
WHAT YOU WILL LEARNnovice path
Identify an exact-vehicle oil approval instead of choosing oil by viscosity alone.
Use a torque wrench correctly and understand why a click is a stop signal, not a target to repeat.
Recognise the N43 cartridge filter, its three replaceable O-rings and the drain-plug sealing ring.
Raise and support a vehicle only with verified lifting points and rated equipment.
Validate an oil service with an electronic level reading, a two-stage leak inspection and a durable service record.
BMW’s wider minor-service scope also includes the microfilter, a parking-brake check and third-oil-change decisions. The E91 cabin-microfilter journey is already available; brake, air-filter and spark-plug work stay separate until their own exact procedures are released.
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%0/8 required items confirmed
Required before start12
part
Oil-filter kit · BMW 11 42 7 508 969 or verified equivalent
verified
The exact N43 service replaces the element and all three filter O-rings.
OEM / REFERENCE PART NUMBER11427508969BMW model/build match — VIN confirmation pending
What exactly should I buy?
Use the exact Genuine BMW reference below to anchor the part identity and appearance. A cheaper equivalent is fine when its own manufacturer catalogue cross-references BMW 11 42 7 508 969 and the supplied kit/seal set matches the procedure. A retailer result merely containing the OE number is not enough.
Copper drain-plug sealing ring A12×17-CU · BMW 07 11 9 963 151
verified
BMW requires a new drain-plug sealing ring; the A12×17-CU reference is mapped to the E91 LCI N43 application.
OEM / REFERENCE PART NUMBER07119963151
What exactly should I buy?
Use the Genuine BMW reference below to anchor the part identity. This requirement is only the copper sealing ring, not automatically a complete drain plug. A cheaper ring is acceptable when its manufacturer data states 12 mm inner diameter, 17 mm outer diameter, about 1.5 mm thickness, copper material and an explicit BMW 07 11 9 963 151 cross-reference.
BMW's handbook defines the accepted petrol-engine Longlife specifications and viscosity classes; the exact N43/B20 service fill is 4.25 L.
For this 08/2009 BMW 3 Series handbook, petrol engines list BMW Longlife-01 and Longlife-01 FE as preferred, with Longlife-04 also permitted. The handbook permits SAE 0W-40, 0W-30, 5W-40 and 5W-30. Confirm that the current manufacturer label or official product data sheet lists the relevant BMW Longlife specification. Viscosity alone is not enough.
tool
86 mm × 16-point oil-filter cap wrench
verified
BMW tool 11 9 240 maps to current 86 mm × 16-flute manual cap wrenches.
Match the 86 mm × 16-point/flute profile before buying. BMW special tool 11 9 240 maps to current equivalents; drive size can differ between brands, so make sure it also matches your ratchet/torque-wrench setup.
tool
Calibrated torque wrench with 25 Nm inside its working range
verified
The filter cap and drain plug both have controlled 25 Nm tightening values.
tool
Metric socket/bit set for the installed drain plug and undertray
corroborated
The undertray and installed drain-plug head must be inspected and matched without rounding fasteners.
tool
Rated lift, ramps, or trolley jack plus two rated support stands
verified
The drain plug is accessed from below; the car must be supported by rated equipment at verified points.
tool
Two wheel chocks
verified
Unlifted wheels must be chocked before raising the vehicle.
tool
Seal-able drain pan with at least 7 L capacity
verified
Used oil must be captured in a suitable container and kept out of drains and soil.
tool
Clean funnel and graduated measuring jug
corroborated
Measured filling prevents contamination and overfill.
tool
Inspection light
corroborated
Both sealing locations must be inspected for active leaks.
tool
Nitrile gloves and safety glasses
corroborated
Hot oil, dirt and splash are predictable hazards.
Conditional2
part
M12×1.5 oil-drain plug
corroborated
A damaged plug cannot be safely reused.
Only if: Buy only after VIN confirmation if the installed plug or threads are damaged.
tool
BMW-compatible diagnostic tool with CBS service reset
corroborated
CBS should only be reset when the service was Due/Recommended and the work has been completed.
Only if: Needed if reset is due and no VIN-matched BMW cluster procedure is available.
SAFETY & DISPOSAL
Plan the finish before you drain the oil
Never work under a vehicle supported only by a jack. Use the verified lifting points and rated stands, ramps or a lift.
Wear gloves and safety glasses, keep absorbent material ready, and avoid contact with hot engine oil.
Capture used oil in a clean sealable container. Do not pour it into a drain, toilet, street drain or onto soil.
In the Netherlands, used engine oil and the used oil filter are KCA (klein chemisch afval) and should be taken separately to the municipal waste/recycling point.
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.
PREPARESTEP 1 / 14
WORKSHOP RELEASEDcritical
Confirm the car and decide what this service includes
Prevent a plausible-looking guide from being applied to the wrong engine, build or service event.
+
No visual needed for this step
Follow the written checks and use the linked sources when you need more context.
Critical safety step
Read the entire step, including every stop condition, before marking it complete.
Stop and get help if
The engine code is not N43B20, or the car is not an E91 320i.
The VIN/build cannot be confirmed well enough to purchase parts.
An oil-pressure warning, heavy active leak, fuel smell in the oil or metallic debris is already present; diagnose before routine servicing.
DO THIS~10 min
Open the Garage vehicle and confirm BMW 3 Series Touring, E91 LCI, 320i, N43B20 and manual transmission. Do not continue from the model badge alone.
Record the VIN’s final seven characters and production month. Use BMW’s VIN-specific owner guide and the parts seller’s VIN check for final fitment.
Read the current CBS oil-service status before touching the car and record whether it says Due/Recommended, a future date/distance, or no oil-service request.
Check the prior service history. If this is every third engine-oil change, flag the engine air filter and spark plugs for separate procedures; BMW’s service scope also calls for a microfilter and parking-brake function check.
If the engine, VIN/build or service history does not match, stop and create a corrected vehicle record instead of adapting this guide by guesswork.
LEARN AS YOU GO
E91 describes the Touring chassis; N43B20 identifies the engine family that controls the oil-system procedure and specifications.
CBS is a service-decision system. A physical oil change and a CBS reset are separate actions.
YOU ARE DONE WHEN
The exact vehicle identity and build are recorded.
The pre-service CBS state and whether this is a third oil service are recorded.
IF SOMETHING GOES WRONGRecovery path
If the Garage record is wrong, correct it first and reload the vehicle-specific procedure.
If service history is missing, treat supplementary items as inspection decisions, not automatic replacements.
