Is the B47 more reliable than the N47?

Generally yes. The B47 has an improved timing chain design and updated injectors. However, injector issues still occur, particularly after 80,000 miles.

How much does B47 injector replacement cost?

A set of four remanufactured B47 injectors costs approximately £500-£700. Including labour (2-3 hours), total cost is typically £700-£1,000.

Can I use N47 injectors in a B47?

No. The B47 uses different injectors with different flow rates and calibration codes. Always use the correct part number for your specific B47 variant.

Does the B47 have the same timing chain issues as the N47?

The B47 has a significantly improved timing chain design with the chain at the front of the engine. While not immune to wear, it is far less problematic than the N47.

How much does it cost to replace injectors?

Replacement typically costs £150–£350 per injector depending on brand and engine. A full set of four with professional fitting usually costs £600–£1,200.

Can I drive with a faulty injector?

Driving with a faulty injector can cause engine damage, increased fuel consumption, DPF contamination, and oil dilution. We recommend diagnosis and replacement as soon as possible.

Do new injectors need coding?

Some vehicles require injector coding after replacement using manufacturer-specific diagnostic tools. Many Bosch solenoid units are plug and play. Check your engine guide for specific requirements.

Why is my diesel injector knocking?

Diesel injector knocking is typically caused by worn nozzle tips that alter the fuel spray pattern, leading to harsher combustion. Carbon buildup, incorrect injection timing, and high fuel pressure can also contribute. A professional leak-off test can confirm whether injectors are the cause.

Can a bad injector cause white smoke?

Yes. A faulty injector that dribbles fuel instead of atomising it causes incomplete combustion, producing white or grey smoke. This is especially noticeable on cold starts and typically clears as the engine warms up.

How long do diesel injectors last?

Most diesel injectors last between 80,000 and 150,000 miles depending on fuel quality, driving conditions, and maintenance. Regular fuel filter changes and using quality diesel can extend their lifespan.

Will injector cleaner fix misfire?

Injector cleaner may help with minor carbon deposits, but it cannot fix worn nozzles, failed solenoids, or internal seal leaks. If misfire persists after using cleaner, professional testing and likely replacement is needed.

BMW B47 Injector Problems: Fault Codes, Symptoms & Repair Advice

Updated for 2026 diagnostics & repair guidance

Common failure compared to BMW N47 & Mercedes OM651 injector faults.

The B47 diesel engine is widely used in the BMW 1, 2, 3, 5 Series, X1, and X3 from 2014 onwards. Over time, fuel injectors may develop faults that affect performance, starting, and emissions. This guide helps you diagnose injector issues and determine when replacement is required.

OEM tested & calibrated12-month warrantyFree UK deliveryNo coding required (most models)

OEM Tested
12-Month Warranty
Free UK Delivery

Registration Lookup Find Matching B47 Injector

Drivers also ask

Quick Diagnosis

If your B47 engine shows:

rough idle
hard starting
white or black smoke
knocking or ticking noise
reduced fuel economy

A faulty injector may be the cause. Continue below to confirm symptoms and solutions.

Can You Drive With This Problem?

Driving short distances may be possible, but continued use can cause:

piston damage
turbo contamination
fuel dilution of engine oil
catalytic converter damage

Prolonged driving may lead to major engine failure.

Typical Repair Costs (UK)

Average costs for injector-related repairs:

£180 - £350

Per Injector

£700 - £1,200

Full Set (4)

£120 - £300

Labour

Early replacement prevents costly engine damage.

Common Injector Failure Symptoms

Owners frequently report:

Rough idle with vibration

Worn B47 injector nozzles cause uneven fuel delivery, resulting in noticeable engine vibration at idle that may worsen in cold weather.

Black smoke under heavy load

Over-fuelling from a worn injector produces black smoke visible in the mirrors during hard acceleration or towing.

Check engine light with misfire codes

The B47's sensitive ECU quickly detects injector imbalance and logs misfire codes, often accompanied by reduced engine power.

Increased DPF regeneration frequency

Faulty injectors produce more soot, forcing the DPF to regenerate more often. Frequent short trips compound this issue.

Fuel smell in engine oil

A leaking injector allows diesel to pass the piston rings and mix with engine oil. Check the dipstick — if oil level is rising and smells of diesel, suspect injectors.

Full symptom guide White smoke guide

Fault Codes Linked to Injector Issues

Common diagnostic codes include:

P0201-P0204Injector circuit malfunction (cylinders 1-4)

P0300Random/multiple cylinder misfire detected

P0301-P0304Specific cylinder misfire detected

P2BAENOx sensor signal implausible (secondary injector effect)

P0087Fuel rail pressure too low

Misfire diagnosis guide

How to Diagnose B47 Injector Faults

Follow this step-by-step testing approach to identify the faulty injector:

1
Read fault codes
Connect an OBD-II scanner and note any injector-related codes (P0201–P0204, P2146, P2149). This identifies which cylinder is affected.
2
Perform a leak-off test
Disconnect the fuel return pipes and route into measuring containers. Run the engine at idle for 60 seconds. Compare volumes per cylinder against manufacturer spec.
3
Listen for injector tick
Use a mechanic's stethoscope on each injector body. A dead or irregular tick indicates a stuck or failing solenoid.
4
Check fuel rail pressure
Monitor live fuel rail pressure data via diagnostic tool. Low pressure can mimic injector symptoms and may indicate a fuel pump issue instead.
5
Inspect for external leaks
Check around injector seals for signs of fuel or combustion gas leakage. Black carbon deposits indicate a blown seal.
6
Cylinder balance test
Use diagnostic software to run a cylinder contribution test. This electronically disables each injector in turn to measure its effect on engine speed.

Full leak-off test guide Injector coding guide

Why B47 Injectors Fail

Common causes include:

fuel contamination
high-pressure wear cycles
carbon buildup
poor fuel quality
internal valve wear

Professional remanufacturing restores spray pattern and pressure accuracy.

When Replacement Is Required

Injector replacement is recommended if:

leak-off test fails
misfire persists after coding
excessive return flow detected
spray pattern fails testing
vehicle enters limp mode

B47 Repair Advice

B47 injectors must be coded using ISTA+ or compatible BMW diagnostic software. The B47 uses a different injector clamp design to the N47 — ensure you use the correct tooling. Check for fuel contamination before fitting new injectors.

Remanufactured (Recommended)

OEM-spec rebuild with new nozzles, seals, and solenoids. Full flow testing. 12-month warranty. 40–60% less than new.

Brand New OEM

Factory-fresh from Bosch, Delphi, or Siemens. Highest cost but zero previous wear. Best for low-mileage vehicles.

Vehicles Using the B47 Engine

This engine is commonly found in:

BMW 118d

F20/F40 · 2015-present

BMW 218d

F22/F44 · 2015-present

BMW 318d

F30/G20 · 2015-present

BMW 320d

F30/G20 · 2015-present

BMW 520d

G30 · 2017-present

BMW X1 18d

F48 · 2015-present

BMW X3 20d

G01 · 2017-present

Professional Installation Tip

Always:

replace copper sealing washers
torque injectors to manufacturer specification
clean injector seats before installation
code injectors after installation (if required)

Leak-off test guide Injector coding guide

Compatible Injector Part Numbers for B47

The following injector part numbers are commonly associated with B47 engines:

Bosch

0445110655

Bosch injector for B47D20 (standard applications)

View details

Bosch

0445110656

Bosch injector for B47D20 (high-output variant)

View details

BMW

13538511144

BMW OE reference number for B47 injector

View details

B47 Injectors — Shop Now

In-stock injectors listed first for fastest delivery:

BMW 1 SERIES ( 118D E8X) 2L 2004-2009 Diesel Injector

£90.00

In StockNext-day delivery12 months

BMW 1 SERIES ( 118d M Sport F20) 2L 2012-2013 Diesel Injector

£99.90

In StockNext-day delivery12 months

BMW 1 SERIES ( 118d M Sport E81) 2L 2007-2012 Diesel Injector

£99.90

In StockNext-day delivery12 months

BMW 1 SERIES ( 118d M Sport Auto F20) 2L 2015-2019 Diesel Injector

£99.90

In StockNext-day delivery12 months

BMW 1 SERIES ( 118d M Sport Auto F21) 2L 2015-2019 Diesel Injector

£99.90

In StockNext-day delivery12 months

BMW 1 SERIES ( 118d M Sport F21) 2L 2015-2019 Diesel Injector

£99.90

In StockNext-day delivery12 months

BMW 1 SERIES ( 118d M Sport E87) 2L 2007-2009 Diesel Injector

£99.90

In StockNext-day delivery12 months

BMW 1 SERIES ( 118d M Sport Auto F20) 2L 2012-2013 Diesel Injector

£99.90

In StockNext-day delivery12 months

View all B47 injectors

These injectors are commonly used with the B47 engine. Confirm compatibility using your engine code or registration lookup before ordering. Our team can verify the correct part for your specific vehicle.