Genuine BMW & MINI OEM Spark Plug Ignition Plug 12120040551 for B38 B46 B48 B58 Turbo Petrol - Fits 1 2 3 4 5 6 7 Series 116i 118i 120i 125i

BMW MINI OE Ignition Plug 12120040551 for B-Series Turbo Petrol Engines

Keep your BMW or MINI running faultlessly with this factory-spec ignition plug, part number 12120040551. Ideal for B38, B46, B48 and B58 engines, this original equipment plug delivers clean combustion, crisp throttle pick-up and dependable starting on both standard and tuned cars. We use these in-house at MJ Modifications and customer feedback has been outstanding for curing hesitation, erratic idle and intermittent misfires while maintaining strong performance under boost.

Perfect for preventative maintenance, servicing or when chasing down fault codes related to ignition quality, this OE plug offers the reliability, longevity and exact fit you expect from a BMW branded component. If your turbo petrol BMW or MINI feels flat, surges under load or stumbles at low rpm, fresh plugs are a proven fix that brings back smoothness and confidence.

Why choose this OE plug

• Original BMW part for precise fitment and correct heat specification
• Strong spark stability under boost for B38, B46, B48 and B58 engines
• Reduces misfire, hesitation and rough running caused by tired plugs
• Restores smooth idle, responsive acceleration and consistent power
• Road and track ready reliability with OEM build quality

In the box

• 1 x BMW OE ignition plug 12120040551

Order the quantity required for your engine configuration and cylinders.

Vehicle applications

Suits BMW and MINI models using B38, B46, B48 and B58 petrol turbo engines, including but not limited to:

• BMW 1 Series F20 F21 LCI 116i, 118i, 120i, 125i, M140i
• BMW 2 Series F22 F23 218i, 220i, 230i, M240i
• BMW 2 Series Active Tourer F45 and Gran Tourer F46 216i, 218i, 220i, 225i, 225xe
• BMW 3 Series F30 F31 F34 LCI 318i, 320i, 330i, 330e, 340i
• BMW 3 Series G20 320i 1.6
• BMW 4 Series F32 F33 F36 418i, 420i, 430i, 440i
• BMW 5 Series G30 G31 520i, 530i, 530e, 540i
• BMW 6 Series G32 GT 630i, 640i
• BMW 7 Series G11 G12 730i, 740i, 740e and derivatives
• BMW X1 F48 18i, 20i, 25i, 28i
• BMW X2 F39 18i, 20i, 25i, 28i
• BMW X3 G01 20i, 30i, M40i
• BMW X4 G02 20i, 30i, M40i
• MINI F54 Clubman, F55 5 Door, F56 3 Door, F57 Convertible, F60 Countryman Cooper, Cooper S, JCW and selected One models with B38 or B48 engines

Search-friendly terms

BMW ignition plug 12120040551, B48 replacement plugs, B58 plug set, B38 spark plug upgrade, BMW 330i ignition plug, BMW 540i plug change, BMW 740i plug, 320i service plug, 116i replacement plug, MINI JCW spark plug, MINI Cooper S B48 ignition plug, BMW 2.0 turbo spark plug, BMW 3.0 turbo spark plug, OE BMW plug, original equipment ignition plug for BMW and MINI.

Service advice

Replace all plugs together for balanced performance across cylinders. Install with correct torque and follow BMW service procedures. A fresh set is a smart move before a remap or any performance upgrade to ensure reliable ignition under load.

Part number

12120040551

Brand

BMW

Installation and support

Professional fitting available at MJ Modifications in Warwickshire. For a quote or to book, email info@mjmodifications.co.uk. Our customers consistently report smoother running and zero misfires after replacing worn plugs with this OE unit.

Fitment check

We verify compatibility before dispatch. Add your UK registration or the last 7 digits of your VIN at checkout so we can confirm this is the correct plug for your vehicle.

Warranty

Two years manufacturer warranty for UK customers and one year for international customers when a VIN is provided at checkout on compatible vehicles.