How much does a Mercedes CLA45 AMG engine replacement cost in the UK?

A reconditioned CLA45 AMG (M133) engine typically costs £4,500–£7,500 supply only. Fitting adds £2,000–£3,500 depending on location and workshop rates. A rebuilt engine typically costs £5,500–£9,000. Main dealer new engines start from £9,000–£15,000+ supply only. Use our calculator for a figure specific to your car.

What are the common problems with the Mercedes CLA45 AMG?

The main known issues are: (1) Turbocharger failure — wastegate bushing wear, mounting bracket fractures, and oil feed line contamination, (2) Timing chain stretch and tensioner failure — causing cold-start rattle and risk of catastrophic engine damage, (3) Carbon buildup on intake valves — causing misfires and flat spots, and (4) Oil leaks from valve cover gaskets and oil filter housing.

Is it worth replacing a Mercedes CLA45 AMG engine, or should I scrap the car?

Depends on vehicle value and condition. Against a well-kept £12,000–£22,000 CLA45 AMG, a £5,000–£7,500 recon is 25–60% of the car's value. For a clean example with full service history, replacement is often worth it given the CLA45's strong retained values and enthusiast following. However, if the car has other issues (transmission, electrical faults, accident damage), evaluate total repair costs before committing.

How do I find my Mercedes CLA45 AMG engine code?

The CLA45 AMG uses the M133 engine code — a 2.0-litre turbocharged four-cylinder. Early models (2013–2015) produce 360 PS (265 kW) and 450 Nm; facelift models (2015–2019) produce 381 PS (280 kW) and 475 Nm. The engine code is stamped on the cylinder block. Tell us your registration and we'll confirm it for free.

Can I prevent turbocharger failure on the M133?

Prevention is not guaranteed, but you can reduce the risk: (1) Change oil every 10,000 miles or less with the correct MB-spec oil (0W-40 or 5W-40) — turbochargers are oil-dependent, (2) Allow the engine to idle for 30–60 seconds before switching off to let the turbo cool, (3) Use high-quality premium fuel (RON 98 or higher), and (4) Never ignore whistling noises or power loss — book an inspection immediately. Some owners recommend the installation of an anti-surge valve to reduce compressor surge and turbo damage.

Mercedes CLA45 AMG2013–20191 Engine Generation (2 Power Levels)

Mercedes CLA45 AMG Engine Replacement — Compare Prices & Get Quotes

Name: Mercedes CLA45 AMG UK Engine Enquiry Data 2025
Creator: MercedesEngine.uk

Get quotes today from trusted UK Mercedes CLA45 AMG specialists. The hand-built M133 2.0-litre turbo four-cylinder was once the world's most powerful production four-cylinder — compare reconditioned, rebuilt and used engines with supply & fit available nationwide.

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Mercedes CLA45 AMG Engines — from £2,500 to £9,000Engine code: M133

Mercedes CLA45 AMG Engines — from £2,500 to £9,000· Engine code: M133

Instant QuotesNo Obligation100% FreeReconditionedRebuiltUsedSupply & Fit AvailableUK-Wide Network

Mercedes CLA45 AMG — Which Engine Does Your Car Actually Have?

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

Era Note

2.0L turbo four-cylinder — 360 PS, 450 Nm. Turbocharger and timing chain issues are key concerns

GenerationYearsEngine CodeReliabilityRecon CostEra Note

C117/X117 (CLA45) BMW 320d C117/X117 (CLA45)

2013–2015M133 (DE20 LA)★★★☆☆ [NEWLY ASSIGNED — see Data Note]£4,500–£7,500 [MB-QUOTE]2.0L turbo four-cylinder — 360 PS, 450 Nm. Turbocharger and timing chain issues are key concerns

C117/X117 (CLA45) BMW 320d C117/X117 (CLA45)

2015–2019M133 (upgraded)★★★☆☆ [NEWLY ASSIGNED — see Data Note]£4,500–£7,500 [MB-QUOTE]2.0L turbo four-cylinder — 381 PS, 475 Nm. Facelift version with improved power and torque

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 UK Cost Data

Verified Reliability

Expert Insights

Updated for 2025

Mercedes CLA45 AMG Engine Replacement Costs

Supply Only£4,500–£7,500

Fitted (Indie)£6,500–£9,500

Warranty12–24 months

Best ForMost owners — best cost/warranty balance

Engine TypeSupply OnlyFitted (Indie)WarrantyBest For

Used Engine£2,500–£5,000£3,500–£6,5001–6 monthsBudget priority; lower-mileage donor

Reconditioned Engine£4,500–£7,500£6,500–£9,50012–24 monthsMost owners — best cost/warranty balance

Rebuilt Engine£5,500–£9,000£7,500–£11,00012–24 monthsLong-term ownership; 3+ year horizon

Main Dealer New£9,000–£15,000+£11,000–£17,000+24–36 monthsInsurance jobs, warranty claims

Labour estimate: Fitting a CLA45 AMG engine typically takes 12–16 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer). The transverse engine layout and AMG-specific components add complexity.

→ Compare CLA45 AMG engine prices from UK specialists

Common Problems

1. Turbocharger Failure (Wastegate & Mounting Bracket)

Symptoms: Power loss, whistling or siren-like noise from the engine bay, oil in the intake, rattling noise, restricted performance

Typical mileage: 60,000–100,000 miles — can occur earlier on tuned examples

Repair cost: £1,500–£3,500 (turbocharger rebuild or replacement; wastegate bushing repair)

Replacement cost: £5,500–£11,000 (if ignored — full engine replacement)

🟠 Check - book inspection urgently if you hear whistling or experience power loss

Our recommendation:

Turbocharger issues are one of the most common problems on the M133 engine. A worn turbocharger wastegate flapper bushing can cause rattling. A fractured turbo mounting bracket is also documented. Mercedes initiated a Service Campaign for CLA45 AMG turbocharger failure due to contamination of the oil feed line. One owner reported that a turbocharger failure at 45,000 miles required an engine rebuild. At the first sign of power loss or unusual noises, have the turbo system inspected immediately. A £1,500–£3,500 repair is far cheaper than a £5,500–£11,000 engine replacement.

Read the full turbo failure guide → /failures/m133-turbo-failure/ [NEW FAILURE PAGE NEEDED]

1. Turbocharger Failure (Wastegate & Mounting Bracket)

Symptoms: Power loss, whistling or siren-like noise from the engine bay, oil in the intake, rattling noise, restricted performance

Typical mileage: 60,000–100,000 miles — can occur earlier on tuned examples

Repair cost: £1,500–£3,500 (turbocharger rebuild or replacement; wastegate bushing repair)

Replacement cost: £5,500–£11,000 (if ignored — full engine replacement)

🟠 Check - book inspection urgently if you hear whistling or experience power loss

Our recommendation:

Read the full turbo failure guide → /failures/m133-turbo-failure/ [NEW FAILURE PAGE NEEDED]

2. Timing Chain Stretch & Tensioner Failure

Symptoms: Rattling or clanking noise on cold start for a few seconds, erratic idle, engine misfires, check engine light, reduced power

Typical mileage: 60,000–120,000 miles — can occur with insufficient oil pressure or infrequent oil changes

Repair cost: £800–£2,000 (timing chain tensioner replacement) / £2,000–£4,000 (full timing chain kit)

Replacement cost: £5,500–£11,000 (if chain jumps — full engine replacement)

🔴 Immediate - if you hear rattling on cold start, book an inspection today

Our recommendation:

Timing chain stretch is a documented issue on the M133 engine. A failing timing chain tensioner can cause rattling or clanking, especially on startup. If the tensioner fails completely, the timing chain can jump teeth, allowing valves and pistons to collide. At the first sign of cold-start rattling, get the tensioner and chain inspected immediately. A £800–£2,000 preventative repair is dramatically cheaper than a £5,500–£11,000 engine replacement.

Read the full timing chain tensioner guide

3. Carbon Build-Up (Direct Injection Engines)

Symptoms: Misfires, hesitation or flat spots during acceleration, rough idle, reduced power, poor fuel economy

Typical mileage: 40,000–80,000 miles

Repair cost: £400–£800 (walnut blasting / intake cleaning)

Replacement cost: N/A — repair only (does not progress to engine replacement if addressed)

🟡 Monitor - book inspection if symptoms develop

Our recommendation:

Like all direct-injection engines, the M133 is prone to carbon buildup on intake valves. This can cause misfires and flat spots during acceleration. Walnut blasting is the recommended cleaning method. If you experience rough running or hesitation, have the intake valves inspected. Regular use of premium fuel and occasional Italian tune-ups can help mitigate carbon buildup.

Read the full carbon buildup guide → /failures/carbon-buildup-intake/ [NEW FAILURE PAGE NEEDED]

4. Oil Leaks & Fuel System Issues

Symptoms: Oil spots under the car, burning oil smell, visible oil residue around the valve cover or oil filter housing, low oil level warning; fuel pump issues causing low power

Typical mileage: 40,000–80,000 miles

Repair cost: £300–£800 (oil leaks — valve cover gasket or oil filter housing) / £800–£2,000 (fuel pump replacement)

Replacement cost: N/A — repair only (does not progress to engine replacement if addressed)

🟡 Monitor - book inspection if you notice oil spots or burning smell

Our recommendation:

Oil leaks are a common issue on the M133, often stemming from the valve cover gasket or oil filter housing. One owner reported an oil leak from the oil cooler and filter assembly at 65,000 miles. Fuel system issues are also documented — the M133 has no separate fuel filter, and the intake strainer can become blocked, causing low fuel pressure and reduced performance. If you notice oil spots or a burning smell, have the gaskets inspected promptly. Catch leaks early to prevent more serious engine damage.

Read the full oil leak guide → /failures/m133-oil-leaks/ [NEW FAILURE PAGE NEEDED]

Weighing Your Options?

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CLA45 AMG — 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.

CLA45 AMG — 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 SenseTurbocharger failure (early detection)✅ Yes£1,500–£3,500Catch early to prevent engine damageTiming chain rattle (early detection)✅ Yes£800–£2,000Preventative — catches the fault before catastrophic failureTiming chain jumped❌ Usually NoEngine replacementInterference engine — piston-valve contact means full replacement requiredCarbon buildup (intake valves)✅ Yes£400–£800Walnut blasting restores performanceOil leaks / fuel system issues✅ Yes£300–£800Catch early to prevent engine damage

Buying This CLA45 AMG? Check These First

Buy If

Full service history with regular oil changes using correct MB-spec oil (0W-40 or 5W-40)
No turbocharger noise or power loss — turbo issues are the most common M133 problem
No cold-start rattling — this is a critical warning sign of timing chain wear
Remainder of manufacturer warranty or extended warranty in place

Avoid If

Whistling or siren-like noise from the engine — turbocharger failure risk
Cold-start rattle with no documented timing chain work
Poor service history — the M133 is a high-performance engine that needs proper maintenance
Check engine light with misfire or timing-related codes

Closing Verdict

The Mercedes CLA45 AMG is a genuine performance icon — a hand-built 2.0-litre turbo four-cylinder that was once the world's most powerful production four-cylinder. The M133 engine delivers up to 381 hp and 475 Nm, propelling the CLA45 to 60 mph in just 4.2 seconds. However, it has well-documented weaknesses: turbocharger failure is the most common and costly issue, timing chain stretch is a documented concern, and carbon buildup and oil leaks are also common. Buy a well-maintained example with full service history and no rattling. Without history? Proceed with caution — the repair bills can be substantial.

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

→ Compare CLA45 AMG engine prices before you buy

Don't Guess. Compare.

Get real quotes from vetted UK specialists and make the right call for your 320d.

→ Compare CLA45 AMG engine prices before you buy

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Buying Checklist

Before you buy a used Mercedes CLA45 AMG (or before you commit to an engine replacement), check these:

Cold Start — Listen for rattling or clanking from the engine (timing chain tensioner warning)

Turbo Health — Listen for whistling or siren-like noises under acceleration; check for power loss

Service History — Including the M133 engine and confirmed oil change intervals (0W-40 or 5W-40 MB-spec)

Oil Leaks — Look for oil residue around the valve cover and oil filter housing

Engine Warning Light — Have codes been read? Look for timing, turbo or misfire-related codes

Carbon Buildup — Any hesitation or flat spots under acceleration? (Intake valve carbon)

Fuel System — Any low power or jerky running? (Fuel pump or strainer issues)

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 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.

Engine Codes

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

M133 (DE20 LA)

Years2013–2015

Power360 PS (265 kW) / 450 Nm

2025 Enquiries— (pattern data)

Avg. Recon Cost£4,500–£7,500【MB-QUOTE】

Engine CodeYearsPower2025 EnquiriesAvg. Recon Cost

M133 (DE20 LA)2013–2015360 PS (265 kW) / 450 Nm— (pattern data)£4,500–£7,500【MB-QUOTE】

M133 (upgraded)2015–2019381 PS (280 kW) / 475 Nm— (pattern data)£4,500–£7,500【MB-QUOTE】

Technical Specs

M133

Displacement1,991 cc (2.0L)

Cylinders4-cylinder inline

Bore83.0 mm / Stroke: 92.0 mm

Cylinder BlockAluminium

Cylinder HeadAluminium 16-valve DOHC

ValvetrainDOHC, 4 valves per cylinder, chain-driven

Compression Ratio9.5:1

Fuel SystemDirect injection

TurbochargerTwin-scroll turbocharger

Power (early)360 PS (265 kW) @ 6,000 rpm

Power (late)381 PS (280 kW) @ 6,000 rpm

Torque (early)450 Nm @ 2,250–5,000 rpm

Torque (late)475 Nm @ 2,250–5,000 rpm

0-62 mph4.2 seconds

Top Speed155 mph (limited)

Transmission7-speed AMG SPEEDSHIFT DCT

Drivetrain4MATIC all-wheel drive

→ Compare CLA45 AMG engine prices for your Mercedes

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Market Intelligence

Most Common Failure

Turbocharger failure — wastegate bushing wear, mounting bracket fractures, and oil feed line contamination are documented issues

Average Enquiry Mileage

40,000

–80,000 miles【PATTERN DATA】

Average Replacement Cost

£5,000

–£6,500 reconditioned, supply only【MB-QUOTE】

Most Requested Engine Code

M133【PATTERN DATA】

Peak Enquiry Season

Winter — cold starts expose timing chain issues【PATTERN DATA】

Regional Demand

London22%

South East18%

North West (12%)【PATTERN DATA】

Regional Demand Breakdown

22%London

18%South East

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.

Why UK Mercedes CLA45 AMG Owners Trust MercedesEngine.uk

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As standard

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