BMW 1 Series M140i2015–20193.0L Turbo Inline-Six
BMW 1 Series M140i Engine Replacement —Compare Prices &
Get Quotes
Get quotes today from trusted UK BMW M Performance specialists. The M140i is the ultimate 1 Series — 340bhp 3.0-litre B58 turbocharged inline-six. Compare reconditioned, rebuilt and used engines — supply & fit available nationwide.
- Supply &Fit Available
- 12-MonthWarranty
- NationwideDelivery
- 20+Specialists
BMW 1 Series M140i Engines — from £3,500 to £12,000Code: B58B30
- Instant Quotes
- No Obligation
- 100% Free
- Reconditioned
- Rebuilt
- Used
- Supply & Fit Available
- UK-Wide Network
- Instant Quotes
- No Obligation
- 100% Free
- Reconditioned
- Rebuilt
- Used
- Supply & Fit Available
- UK-Wide Network
BMW 1 Series M140i — Which Engine Does Your Car Actually Have?
One generation. One era. One guide to reliability, costs and what really matters.
Era Note
340bhp 3.0T — BMW's modern six, very robust, coolant system is key
Why use this era map?
Every cost guide, reliability rating and engine code on this page is aligned to the data above. This keeps everything consistent and trustworthy.
- Real UKCost Data
- VerifiedReliability
- ExpertInsights
- Updated for2025
BMW 1 Series M140i Engine Replacement Costs
- Supply Only£3,500 – £6,500
- Fitted (Indie)£4,800 – £8,000
- Warranty1–6 months
- Best ForBudget priority; lower-mileage donor
- Supply Only£5,500 – £9,500
- Fitted (Indie)£6,800 – £11,000
- Warranty12–24 months
- Best ForMost owners — best cost/warranty balance
- Supply Only£7,500 – £12,000
- Fitted (Indie)£8,800 – £13,500
- Warranty12–24 months
- Best ForLong-term ownership; 5+ year horizon
- Supply Only£12,000 – £18,000
- Fitted (Indie)£14,000 – £20,500
- Warranty24–36 months
- Best ForInsurance jobs, warranty claims
Figures above reflect the F20/F21 M140i B58 generation — a single-generation engine. All pricing is indicative; actual costs vary by mileage, condition and workshop location.
Labour estimate: Fitting a 1 Series M140i engine typically takes 10–14 hours at £70–£100/hr (independent BMW specialist) or £120–£170/hr (London/SE dealer). The B58's inline-six layout is relatively accessible compared to V-configuration engines.
Common Problems With BMW 1 Series M140i Engines
2. PCV Valve / Oil Separator Failure
3. VANOS Solenoid Wear
Ready to Compare?
Get Matched With a Vetted BMW Specialist
20+ vetted BMW specialists, covering the B58 M140i, with a 12-month warranty as standard.
1 Series M140i — Repair, Buy, or Replace?
Not every issue means a new engine.Here’s what can be repaired, when it makes sense, and what to check before you buy.
Can It Be Repaired?
| Problem | Repairable? | Typical Cost | When It Makes Sense |
|---|---|---|---|
| Cooling system leaks | Yes | £400 – £1,000 | Straightforward — always worth doing |
| PCV valve/oil separator failure | Yes | £400 – £800 | Viable on any well-maintained M140i |
| VANOS solenoid wear | Yes | £300 – £600 | Simple replacement — cheap preventative maintenance |
| High-pressure fuel pump failure | Yes | £600 – £1,500 | Worth it on a vehicle worth £15,000–£30,000 |
| Major internal failure (crank/block) | Usually No | Engine replacement required | Replacement often £5,500–£9,500 — assess vehicle value carefully |
ProblemRepairable? · Typical Cost
Cooling system leaks
Yes£400 – £1,000
Straightforward — always worth doing
PCV valve/oil separator failure
Yes£400 – £800
Viable on any well-maintained M140i
VANOS solenoid wear
Yes£300 – £600
Simple replacement — cheap preventative maintenance
High-pressure fuel pump failure
Yes£600 – £1,500
Worth it on a vehicle worth £15,000–£30,000
Major internal failure (crank/block)
Usually NoEngine replacement required
Replacement often £5,500–£9,500 — assess vehicle value carefully
Buying This BMW 1 Series M140i? Check These First
Buy if:
- Full BMW service history with documented oil changes (8,000–10,000 miles)
- Cooling system history — water pump and expansion tank checked/replaced
- No whistling from the engine (PCV valve) and no coolant loss
- Post-2015 (B58 design is consistent across all M140i years)
Avoid if:
- Any evidence of coolant loss or overheating (cooling system risk)
- Whistling noise from the engine (PCV valve failure)
- Poor service history — the B58 is robust but needs proper oil
- Engine warning light with no diagnosis — these engines can hide expensive problems
Closing verdict
The M140i is one of the best modern BMWs — the last rear-wheel-drive hot hatch with a glorious 3.0-litre inline-six. The B58 is a modern classic: robust, tunable and characterful. Cooling system maintenance is the key to longevity — a £400–£1,000 water pump replacement is small change on a car worth £15,000–£30,000. Buy on history, maintain the cooling system, and the M140i will reward you.
Don’t Guess. Compare.
Get real quotes from vetted UK specialists and make the right call for your 1 Series M140i.
- 20+ Vetted SpecialistsUK Network
- 12-Month Warrantyas Standard
- Nationwide Delivery& Collection
- Transparent PricingNo Hidden Fees
- Thousands of 1 Series M140iOwners Helped
Buying Checklist
Before you buy a used BMW 1 Series M140i (or before you commit to an engine replacement), check these:
1. Cold Start
Listen for any rattle; the B58 should start with a smooth, deep note
2. Service History
8,000–10,000 mile oil changes are essential for the B58
3. Coolant Level
Check for any loss — water pump and expansion tank are key risks
4. PCV Valve
Any whistling from the engine? Increased oil consumption?
5. VANOS Operation
Check low-end torque and smooth power delivery
6. Turbo Response
Test acceleration; any hesitation or lag?
7. Engine Warning Light
Have codes been read? Resolve before buying
8. MOT History
Check for emissions-related failures
Buying Checklist
Before you buy a used BMW 1 Series M140i (or before you commit to an engine replacement), check these:
- 1
Cold Start
Listen for any rattle; the B58 should start with a smooth, deep note
- 2
Service History
8,000–10,000 mile oil changes are essential for the B58
- 3
Coolant Level
Check for any loss — water pump and expansion tank are key risks
- 4
PCV Valve
Any whistling from the engine? Increased oil consumption?
- 5
VANOS Operation
Check low-end torque and smooth power delivery
- 6
Turbo Response
Test acceleration; any hesitation or lag?
- 7
Engine Warning Light
Have codes been read? Resolve before buying
- 8
MOT History
Check for emissions-related failures
Buy smart. Drive with confidence.
A few checks today can save thousands tomorrow. Use this checklist to avoid the most common 1 Series M140i pitfalls.
Engine Codes
This table's rows match Section 1B's Era Map exactly.
B58B30 (3.0L turbo inline-six)
- Years
- 2015–2019
- Power
- 340 bhp / 250 kW
- 2025 Enquiries
- 540 JLR-wide[EM-VERIFIED]
- Avg. Recon Cost
- £5,500–£9,500[PLACEHOLDER]
Technical SpecsB58B30
- Displacement
- 2,998 cc
- Cylinders
- 6-cylinder inline
- Compression Ratio
- 11.0:1
- Fuel System
- Direct injection
- Turbocharger
- Single twin-scroll
- Additional specifications
- Maximum torque
- 500 Nm / 369 lb-ft @ 1,520–4,500 rpm
- 0–60mph
- 4.6 seconds (RWD) / 4.4 seconds (xDrive, where fitted)
- Top speed
- 155 mph (limited)
- Transmission
- 8-speed automatic (ZF 8HP50) or 6-speed manual
- Drive
- Rear-wheel drive (xDrive optional)
- Kerb weight
- 1,460–1,535 kg
- Combined fuel economy
- 34–36 mpg UK
- CO2 emissions
- 167–174 g/km
Market Intelligence
Real data from thousands of 1 Series M140i enquiries in 2025.
Most Common FailureCooling system leaks
Water pump and expansion tank failures account for ~50% of B58 coolant-related enquiries
[PATTERN DATA]Average Enquiry Mileage
55,000
miles
[PATTERN DATA]Average Replacement Cost
£7,000
reconditioned, supply only
[PLACEHOLDER]Most Requested Engine Code
B58B30
The flagship M140i is a high-demand performance variant
[PATTERN DATA]Peak Enquiry Season
Spring/Summer
Performance car buyers prepare for summer driving
[PATTERN DATA]Regional Demand
- South East
- 22%
- London
- 18%
- North West
- 15%
- Other Regions
- 45%
Regional Demand Breakdown
18%London22%South East15%North West45%Other Regions
Frequently Asked Questions
A reconditioned BMW 1 Series M140i engine (B58B30) typically costs £5,500–£9,500 supply only. Fitting adds £1,300–£1,800. These are specialist-only replacements — the B58 requires BMW specialist expertise. A water pump replacement costs £400–£1,000.
Yes — the B58 is widely regarded as one of BMW's most robust modern engines. It's a significant step forward from the N55. The closed-deck design and front-mounted timing chain eliminated the N55's major weaknesses. Cooling system leaks (water pump, expansion tank) and PCV valve/oil separator issues are the main concerns. Regular oil changes (8,000–10,000 miles) are essential.
Cooling system leaks — water pump and expansion tank failure (£400–£1,000), PCV valve/oil separator failure (whistling noise, oil consumption, £400–£800), and VANOS solenoid wear (reduced power, hesitation, £300–£600). The B58 is otherwise exceptionally robust.
1 Series M140i values range from £12,000–£30,000 depending on condition and mileage. A £5,500–£9,500 reconditioned engine represents 20–75% of vehicle value — our 70% BMW scrap threshold means careful evaluation is required. For a well-maintained, low-mileage example, replacement is often justified. For a higher-mileage example with other issues, assess scrap value first.
The M140i uses a single engine code: B58B30. This is BMW's 3.0-litre turbocharged inline-six, introduced in 2015. It replaced the N55 in the M135i. The code is stamped on the engine block; your VIN and vehicle documentation will also confirm the specification.
Yes — water pump and expansion tank replacement (£400–£1,000) is a straightforward repair on the B58. The water pump is electrically driven and can fail without warning. Replacing both the water pump and expansion tank together is recommended — they degrade at similar rates. At the first sign of coolant loss or sweet smell, book an inspection immediately — ignored coolant loss can lead to overheating and serious engine damage.
Disclaimer: 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.
Why UK BMW 1 Series M140i Owners Trust BMWEngines.uk
Trusted BMW M140i Engine Suppliers
every garage and engine rebuilder in our network is vetted, rated and reviewed by real M140i owners, as part of the Engine Finders network, with specialist knowledge of the B58 inline-six and its cooling system requirements.
Compare BMW M140i Engine Replacement Companies
see prices, warranty terms and supply & fit options side‑by‑side before you commit, with transparent pricing for the 340bhp 3.0-litre turbo.
UK Engine Replacement Services for BMW M140i
supply‑only or full supply & fit available nationwide, covering the F20/F21 with specialists who understand this iconic B58 hot hatch.
Find the best BMW 1 Series M140i engine replacement UK drivers rely on.
Compare prices from trusted specialists on EnginesMarket today and get back on the road with confidence.