BMW 3 Series 335i2006–20153.0L Twin-Turbo / Twin-Scroll Turbo I6

BMW 3 Series 335i Engine Replacement — Compare Prices & Get Quotes

Get quotes today from trusted UK BMW specialists. Compare reconditioned, rebuilt and used N54 and N55 3.0-litre turbocharged engines for the 3 Series 335i - the game-changing twin-turbo six that redefined BMW performance. Supply & fit available nationwide.

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BMW 3 Series 335i Engines - from £1,500 to £5,500Common codes: N54B30 (Twin-Turbo), N55B30 (Twin-Scroll)

BMW 3 Series 335i Engines - from £1,500 to £5,500· Common codes: N54B30 (Twin-Turbo), N55B30 (Twin-Scroll)

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BMW 3 Series 335i - Which Engine Does Your Car Actually Have?

Four generations. Four eras. One guide to reliability, costs and what really matters.

Era Note

BMW's first mass‑production turbo petrol - HPFP and injector issues are defining weaknesses

GenerationYearsEngine CodeReliabilityRecon CostEra Note

E90/E91/E92/E93 BMW 320d E90/E91/E92/E93

2006–2010N54B30 (3.0L Twin-Turbo I6)★★★½☆ [NEWLY ASSIGNED - see Data Note]£2,800–£4,500 [PLACEHOLDER - confirm vs cost sheet]BMW's first mass‑production turbo petrol - HPFP and injector issues are defining weaknesses

E90/E91/E92/E93 (LCI) BMW 320d E90/E91/E92/E93 (LCI)

2010–2013N55B30 (3.0L Twin-Scroll I6)★★★★☆ [NEWLY ASSIGNED - see Data Note]£2,500–£4,200 [PLACEHOLDER - confirm vs cost sheet]Single twin‑scroll turbo - more reliable than N54, but valve cover and OFHG leaks remain

F30/F31

2011–2015N55B30 (3.0L Twin-Scroll I6)★★★★☆ [NEWLY ASSIGNED - see Data Note]£2,500–£4,500 [PLACEHOLDER - confirm vs cost sheet]F30‑era N55 - same core engine, electric wastegate, revised charge pipe

Why use this era map?

This table is the single source every other section on this page must match. Sections 2, 4, and 6 reference it rather than restating conflicting figures.

Real UK Cost Data

Verified Reliability

Expert Insights

Updated for 2025

BMW 3 Series 335i Engine Replacement Costs

Supply Only£2,800–£4,200

Fitted (Indie)£3,800–£5,500

Warranty12–24 months

Best ForMost owners - best cost/warranty balance

Engine TypeSupply OnlyFitted (Indie)WarrantyBest For

Used Engine£1,500–£2,800£2,300–£4,0001–6 monthsBudget priority; short‑term ownership

Reconditioned Engine£2,800–£4,200£3,800–£5,50012–24 monthsMost owners - best cost/warranty balance

Rebuilt Engine£3,800–£5,500£4,800–£6,80012–24 monthsLong‑term ownership; maximum reliability

Main Dealer New£6,000–£8,500£7,500–£10,50024–36 monthsInsurance jobs; warranty claims; full provenance

Figures above reflect the 335i pricing across generations. The N54 and N55 have broadly similar replacement costs, though N54 engines (with twin turbos) may command a slight premium. Older generations: see the Era Map above for generation-specific pricing. A full engine replacement with labour can cost £9,000–£13,000 for premium vehicles.

Labour estimate: Fitting a 335i engine typically takes 10–14 hours at £75–£110/hr (independent BMW specialist). N54 twin-turbo variants may require additional labour due to turbo system complexity.

→ Compare 3 Series 335i engine prices from UK specialists

Common Problems With BMW 320d Engines

1. High‑Pressure Fuel Pump (HPFP) Failure - N54 (E90, 2006–2010)

Symptoms: Long cranking on cold or hot start, loss of power, engine stalling, engine warning light (limp mode), reduced fuel economy - in extreme cases, the car may leave you stranded.

Typical mileage: 20,000–60,000 miles (some owners experienced multiple failures within a few thousand miles).

Repair cost: £600–£1,200 [PLACEHOLDER] (HPFP replacement).

Replacement cost: N/A - repair only (if caught early).

🔴 Immediate - if you experience long cranking or stalling, book an inspection immediately.

Our recommendation:

HPFP failure is the most notorious issue with the N54 engine. BMW issued recalls covering over 150,000 vehicles in the US for N54 HPFP failures. Symptoms include extended cranking times, particularly when hot, and the car going into limp mode. A failed HPFP can leave you stranded. While replacement is straightforward, the N54's HPFP is a known weak point - budget for it. The N55 uses an updated HPFP design that is more reliable.

1. High‑Pressure Fuel Pump (HPFP) Failure - N54 (E90, 2006–2010)

Symptoms: Long cranking on cold or hot start, loss of power, engine stalling, engine warning light (limp mode), reduced fuel economy - in extreme cases, the car may leave you stranded.

Typical mileage: 20,000–60,000 miles (some owners experienced multiple failures within a few thousand miles).

Repair cost: £600–£1,200 [PLACEHOLDER] (HPFP replacement).

Replacement cost: N/A - repair only (if caught early).

🔴 Immediate - if you experience long cranking or stalling, book an inspection immediately.

Our recommendation:

2. Fuel Injector Failure - N54 (E90, 2006–2010)

Symptoms: Rough idle, misfire, hesitation on acceleration, engine warning light, fuel smell from the engine bay, increased fuel consumption.

Typical mileage: 30,000–80,000 miles (can vary significantly).

Repair cost: £800–£2,000 [PLACEHOLDER] (injector replacement - all six injectors should ideally be replaced as a set with updated index 12 injectors).

Replacement cost: N/A - repair only (if caught early; ignored injector failure can damage the catalytic converter).

🟠 Check - book inspection urgently if misfire or rough running occurs.

Our recommendation:

The N54's piezo direct injectors are a known failure point. BMW released updated injectors (index 12) to address the issue, but failure can still occur on higher-mileage examples. Symptoms include rough idle, misfire, and fuel smell. When replacing injectors, it's strongly recommended to replace all six and have the DME calibrated. A full set replacement typically costs £800–£2,000 including labour - cheaper than dealing with a failed catalytic converter or engine damage.

3. Wastegate Rattle / Turbocharger Failure - N54 (E90, 2006–2010)

Symptoms: Metallic rattling noise from the engine bay during deceleration or at idle, loss of boost pressure, reduced power, engine warning light.

Typical mileage: 40,000–80,000 miles.

Repair cost: £1,500–£3,500 [PLACEHOLDER] (turbocharger replacement or wastegate repair).

Replacement cost: N/A - repair only (if caught early; ignored turbo failure can send debris into the engine).

🟠 Check - book inspection urgently if you hear rattling or notice power loss.

Our recommendation:

The N54's twin turbochargers use wastegate actuators that can develop play over time, causing a characteristic rattle. While not an immediate failure, it indicates wear. BMW extended the warranty on N54 wastegates to 8 years/82,000 miles in some markets. On higher-mileage N54s, turbo replacement is a common expense. The N55's single twin-scroll turbo is more reliable in this regard.

4. Oil Leaks - Valve Cover Gasket & Oil Filter Housing Gasket (N54 & N55)

Symptoms: Oil spots under the vehicle, burning oil smell, low oil level warning, visible oil leak from the top or front of the engine.

Typical mileage: 40,000–80,000 miles (N54 and N55).

Repair cost: £300–£800 [PLACEHOLDER] (valve cover gasket or oil filter housing gasket replacement).

Replacement cost: N/A - repair only (if caught early; ignored oil loss can lead to engine damage).

🟠 Check - book inspection urgently if oil leak is detected.

Our recommendation:

Both N54 and N55 engines are known for oil leaks from the valve cover gasket and oil filter housing gasket (OFHG). The N55's valve cover is particularly prone to warping, requiring full cover replacement. If the OFHG fails, oil can leak onto the serpentine belt, causing it to slip or break - which can then be ingested into the engine through the front crankshaft seal, causing catastrophic failure. A £300–£800 gasket replacement is far cheaper than the consequences of a snapped belt.

5. Water Pump & Thermostat Failure (N54 & N55)

Symptoms: Overheating, coolant loss, engine warning light, electric water pump noise, poor heater performance, the electric water pump may fail without warning.

Typical mileage: 50,000–80,000 miles.

Repair cost: £500–£1,000 [PLACEHOLDER] (water pump and thermostat replacement).

Replacement cost: N/A - repair only (if caught early; ignored overheating can cause head gasket failure).

🟠 Check - book inspection urgently if overheating or coolant loss occurs.

Our recommendation:

Both N54 and N55 use an electric water pump that is a known wear item. BMW's electric water pumps typically fail between 50,000–80,000 miles, often without warning. When it fails, the engine overheats rapidly - and in an aluminium-block engine, that can mean a warped head or blown head gasket. The thermostat often fails at the same time. A £500–£1,000 preventative replacement is cheaper than a £2,000+ head gasket repair.

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BMW 3 Series 335i - Repair, Buy, or Replace?

Every 320d has a story. Make the right call with clear data, real-world costs, and honest guidance from UK specialists.

BMW 3 Series 335i - Repair, Buy, or Replace?

Every 320d has a story. Make the right call with clear data, real-world costs, and honest guidance from UK specialists.

Can It Be Repaired?

ProblemRepairable?Typical CostWhen It Makes SenseHPFP failure (N54)✅ Yes£600–£1,200 [PLACEHOLDER]Worth fixing - a common and well-understood repairFuel injector failure (N54)✅ Yes£800–£2,000 [PLACEHOLDER]Replace all six with updated index 12 injectorsWastegate rattle / turbo failure (N54)✅ Yes£1,500–£3,500 [PLACEHOLDER]Worth fixing on a well-maintained exampleOil leaks (valve cover / OFHG)✅ Yes£300–£800 [PLACEHOLDER]Essential maintenance - always worth doingWater pump failure (N54/N55)✅ Yes£500–£1,000 [PLACEHOLDER]Routine maintenance on higher‑mileage examplesMajor internal failure (crank, bearings)❌ Usually No£2,800–£5,500+Full engine replacement often more cost‑effective

Buying This BMW 3 Series 335i? Check These First

Buy If

Full BMW service history with documented oil changes (every 8,000–10,000 miles)
N54: HPFP replaced with updated part, injectors replaced with index 12 units
N55: Valve cover and OFHG replaced, water pump replaced
Evidence of premium fuel use (98 RON recommended for both engines)

Avoid If

N54: Any sign of long cranking, misfire, or wastegate rattle
N54: No evidence of HPFP or injector replacement on higher‑mileage cars
N55: Any sign of oil leaks or overheating history
No evidence of regular oil changes - both engines are intolerant of neglect

Closing Verdict

The BMW 335i represents a pivotal moment in BMW history - the first mass‑production turbocharged petrol engine (N54) and its refined successor (N55). The N54 offers incredible tuning potential and a sonorous twin‑turbo character, but it comes with well‑documented weaknesses: HPFP, injectors, and turbos. The N55 is more reliable and responsive, with earlier torque delivery, but still suffers from oil leaks and water pump failures. Buy on service history above all else - a well‑maintained 335i of either engine is a rewarding and powerful car; a neglected example can be a financial black hole.

Don't guess.Get the right engine at the right price.

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Buying Checklist

Before you buy a used BMW 3 Series 335i (or before you commit to an engine replacement), check these:

1. Cold Start

Any rattle or wastegate noise? Any long cranking? (HPFP warning on N54)

2. Service History

Regular oil changes (8,000–10,000 miles) - this is non‑negotiable on both engines

3. HPFP / Injector History

N54: Have the HPFP and injectors been replaced with updated parts?

4. Oil Leaks

Check under the vehicle and around the valve cover and oil filter housing

5. Water Pump

Has the electric water pump been replaced? (N54 and N55)

6. Turbo Health

Any rattling, whistling, or loss of boost? (N54 wastegate rattle is common)

7. Running Quality

Any rough idle, hesitation, or misfire? (N54 injector warning)

8. MOT History

Check for emissions‑related failures or any advisory notes

Buy smart. Drive with confidence.

A few checks today can save thousands tomorrow. Use this checklist to avoid the most common 320d pitfalls.

Buy smart. Drive with confidence.

A few checks today can save thousands tomorrow. Use this checklist to avoid the most common 320d pitfalls.

BMW 320d Engine Codes

This table's rows match Section 1B's Era Map exactly.

N54B30 (3.0L Twin-Turbo I6)

Years2006–2010

Power306 PS (225 kW) / 400 Nm

2025 Enquiries- (pattern data)

Avg. Recon Cost£2,800–£4,500 [PLACEHOLDER]

Engine CodeYearsPower2025 EnquiriesAvg. Recon Cost

N54B30 (3.0L Twin-Turbo I6)2006–2010306 PS (225 kW) / 400 Nm- (pattern data)£2,800–£4,500 [PLACEHOLDER]

N55B30 (3.0L Twin-Scroll I6)2010–2015306 PS (225 kW) / 400 Nm- (pattern data)£2,500–£4,500 [PLACEHOLDER]

Technical Specs

N55B30 - 3.0L Twin-Scroll

Displacement2,979 cc

Cylinders6‑cylinder inline

Compression Ratio10.2:1

Fuel SystemDirect injection

AspirationTwin‑turbocharged (parallel)

ValvetrainDOHC with VVT

Displacement2,979 cc

Cylinders6‑cylinder inline

Compression Ratio10.2:1

Fuel SystemDirect injection

AspirationTwin‑scroll single turbocharger

ValvetrainDOHC with VVT

→ Compare 3 Series 335i engine prices for your BMW

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Market Intelligence

Most Common Failure

N54: HPFP failure

the defining weakness of the early 335i

Average Enquiry Mileage

60,000

–90,000 miles

[PATTERN DATA]

Average Replacement Cost

£3,500

reconditioned, supply only

[PLACEHOLDER]

Most Requested Engine Code

N54B30

the original twin-turbo is more commonly sought

[PATTERN DATA]

Peak Enquiry Season

Autumn/Winter

cold starts expose HPFP and wastegate issues

[PATTERN DATA]

Regional Demand

South East22%

London16%

North West (12%) - performance car strongholds

PATTERN DATA

Regional Demand Breakdown

22%South East

16%London

BMW 320d - Frequently Asked Questions

All prices are indicative UK market ranges based on historical quote data from our network of engine specialists. Actual costs vary by variant, engine code, damage severity and workshop location. Use our free comparison tool to get tailored quotes. Every engine supplied through EnginesMarket carries a minimum 12‑month unlimited‑mileage warranty - always confirm terms with your chosen supplier.

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No hidden fees

No Obligation

Get quotes with zero pressure

UK Specialists

20+ vetted experts

12-Month Warranty

As standard

Nationwide Delivery

Supply & fit available