Mercedes-Benz A-Klasse W176
Weaknesses, engine ratings and buying advice
The Mercedes A-Class W176 (2012–2018) was a genuine fresh start — away from the tall "sandwich floor" design towards a sporty compact on the new MFA platform (front-wheel drive, a first for Mercedes in this segment). Engines range from Renault-joint-venture units to hand-built AMG powerplants. Build quality is better than the reputation suggests; engine choice determines long-term happiness.
The volume engine: The M270DE16 1.6T (A 160 at 75 kW, A 180 at 90 kW, A 200 at 115 kW) is the most common. Fundamentally solid, but timing chain stretch from 80,000–120,000 km is the main concern — cold-start rattling is the first symptom. Chain replacement: $1,400–2,500. Ignore the rattle and you risk engine damage. The larger M270DE20 2.0T (A 220 at 135 kW, A 250 at 155 kW) shares the timing chain topic but offers significantly more driving enjoyment. The A 250 Sport with manual gearbox is the sleeper pick for driving fun without AMG pricing.
The AMG: The M133 2.0T in the A 45 AMG (265 kW, facelift 280 kW) is hand-assembled under the "One Man, One Engine" principle. The engine itself is robust — the weak link sits behind it: the 7G-DCT dual-clutch gearbox judders at low speeds and in crawling traffic, a systemic issue across all W176 automatic models, made worse by the A 45's 450 Nm torque. Clutch pack replacement: $2,300–4,000. Software updates help but don't fully resolve it.
Diesels: The OM607 1.5 Renault diesel (A 160 CDI/A 180 CDI, 66–80 kW) is the economy option — low performance, minimal Mercedes feel, cheap to run. The OM651DE18 1.8 CDI and OM651DE22 2.1 CDI (100–130 kW) are in-house engines with solid long-term reliability. DPF clogging is a factor on short trips — same as any modern diesel.
Whole car: Door-edge and wheel arch rust on early build years (2012–2014) — Mercedes provided goodwill repairs at the time but that window is closed. The COMAND/Audio 20 infotainment looks dated by 2026: no wireless Android Auto or Apple CarPlay without aftermarket retrofit. Control arm bushings and drop links wear from 60,000 km with spirited driving.
Test-drive checklist: Cold start: timing chain rattle on M270 = budget for chain replacement. Test 7G-DCT in parking lot traffic — does it judder while manoeuvring? A 45: check for harsh gearchanges under load. Inspect door edges for rust bubbles.
2026 market: A 180 from $9,000. A 250 Sport from $14,000. A 45 AMG: $28,000–38,000, prices stable due to growing collector potential. Pre-facelift (pre-2015) significantly cheaper but higher timing chain risk.
Insider pick: A 250 M270DE20 (2015+) with manual gearbox, or A 45 AMG with documented gearbox service history under 80,000 km — the A 250 manual skips the DCT issue entirely, the A 45 needs full maintenance documentation.
381 PS
A 45 AMG · Benzin
A 45 AMG — Even Sharper
Legendary!120–204 PS
2.1L Diesel Diesel
6 weaknesses
Stay Away!Generations
Engine Overview
The Mercedes-Benz A-Klasse W176 is available with 10 engine variants — from 75 to 387 hp. 1 variants had engine changes — the model year is crucial.
Renault-based small diesel (K9K). Economical but with little power reserve. Prone to EGR fouling and DPF issues under pure short-trip use.
- !! Timing belt instead of chain -- maintenance obligation from 120,000 km
The Renault K9K-based OM607 uses a timing belt that must be replaced every 120,000 km or 6 years. Neglecting the change leads to snapping and severe engine damage.
Symptoms: No noticeable warning before snap -- sudden failure with no advance notice if change is overdue - !! Timing belt interference engine -- total loss risk from 120,000 km
The OM607 is an interference engine with a timing belt (Renault K9K). Mercedes specifies 200,000 km; Renault recommends 120,000 km for the same engine. If the belt snaps, pistons meet valves -- immediate engine destruction.
Symptoms: Usually no warning before snap; sometimes faint squealing or rattling on cold start - !! Injector failure K9K base from 100,000 km
The Renault-based K9K diesel shows known injector weaknesses. Defective injectors cause poor combustion, increased soot production and drastically shorten DPF regeneration intervals.
Symptoms: Rough idle, power loss, black smoke, frequent DPF regeneration, fault codes for individual cylinders
+ 3 more engine weaknesses + vehicle weaknesses
Renault-based small diesel (K9K). Economical but with little power reserve. Prone to EGR fouling and DPF issues under pure short-trip use.
- !! Timing belt instead of chain -- maintenance obligation from 120,000 km
The Renault K9K-based OM607 uses a timing belt that must be replaced every 120,000 km or 6 years. Neglecting the change leads to snapping and severe engine damage.
Symptoms: No noticeable warning before snap -- sudden failure with no advance notice if change is overdue - !! Timing belt interference engine -- total loss risk from 120,000 km
The OM607 is an interference engine with a timing belt (Renault K9K). Mercedes specifies 200,000 km; Renault recommends 120,000 km for the same engine. If the belt snaps, pistons meet valves -- immediate engine destruction.
Symptoms: Usually no warning before snap; sometimes faint squealing or rattling on cold start - !! Injector failure K9K base from 100,000 km
The Renault-based K9K diesel shows known injector weaknesses. Defective injectors cause poor combustion, increased soot production and drastically shorten DPF regeneration intervals.
Symptoms: Rough idle, power loss, black smoke, frequent DPF regeneration, fault codes for individual cylinders
+ 3 more engine weaknesses + vehicle weaknesses
Smaller displacement variant of the OM651. Same technology as the 2.1L but less torque. Known for injector seal issues and timing chain stretch.
- !! Piezo Injector Faults (220/250 CDI) from 80,000 km
Quality issues with Delphi piezo injectors in the 220 CDI and 250 CDI: injectors fail prematurely. A service action replaced piezo injectors with solenoid injectors free of charge.
Symptoms: Strong vibrations under acceleration, rough running, elevated fuel consumption, exhaust smoke - !! Chain Tensioner Failure with Oil Loss from 120,000 km
The OM651 chain tensioner can fail and allow engine oil to escape. Mainly affects vehicles built February–November 2014 (recall). Simplex roller chain increases wear risk.
Symptoms: Light rattling on cold start from the rear of the engine, oil loss, engine warning light - !! Particulate Filter Blockage with Short-Trip Use from 100,000 km
The DPF on the OM651DE18 does not regenerate completely during pure short-trip driving and blocks. A motorway run at least every 2 weeks is required.
Symptoms: DPF warning light, power reduction, engine oil diluted by unburnt fuel
+ 2 more engine weaknesses + vehicle weaknesses
Widely used Mercedes diesel with aluminium block and steel liner. High mileages possible but known for injector seal issues, timing chain stretch and EGR problems.
- !! Chain Tensioner Seal Leaking — Recall
Over 100,000 vehicles recalled: the chain tensioner seal leaks, allowing engine oil to drip onto the exhaust system and potentially ignite.
Symptoms: Dropping oil level, oil smell from engine bay, oily deposits under the vehicle, possible oil fire - !! Timing Chain Stretch (Simplex Chain) from 150,000 km
The OM651 uses a simplex timing chain. With short-trip driving and overdue oil change intervals the chain stretches.
Symptoms: Light rattling noise on cold start from the rear of the engine, no fault code stored - !! Piezo Injector Faults from 80,000 km
Same Delphi piezo injector problems as in the DE18: 220 CDI and 250 CDI variants affected. Mercedes replaced them with solenoid injectors as part of a service action.
Symptoms: Vibrations and rough running especially under acceleration, elevated fuel consumption
+ 3 more engine weaknesses + vehicle weaknesses
Widely used Mercedes diesel with aluminium block and steel liner. High mileages possible but known for injector seal issues, timing chain stretch and EGR problems.
- !! Chain Tensioner Seal Leaking — Recall
Over 100,000 vehicles recalled: the chain tensioner seal leaks, allowing engine oil to drip onto the exhaust system and potentially ignite.
Symptoms: Dropping oil level, oil smell from engine bay, oily deposits under the vehicle, possible oil fire - !! Timing Chain Stretch (Simplex Chain) from 150,000 km
The OM651 uses a simplex timing chain. With short-trip driving and overdue oil change intervals the chain stretches.
Symptoms: Light rattling noise on cold start from the rear of the engine, no fault code stored - !! Piezo Injector Faults from 80,000 km
Same Delphi piezo injector problems as in the DE18: 220 CDI and 250 CDI variants affected. Mercedes replaced them with solenoid injectors as part of a service action.
Symptoms: Vibrations and rough running especially under acceleration, elevated fuel consumption
+ 3 more engine weaknesses + vehicle weaknesses
Modular four-cylinder turbo of the first compact platform generation. Known for timing chain stretch and thermostat issues. Adequate power up to 156 hp.
- !! Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness from 90,000 km
The sealing ring on the camshaft adjuster solenoid fails. Oil creeps by capillary action through the wiring harness and destroys lambda sensors and the ECU. Repair €1,700–€4,000.
Symptoms: Lambda sensor fault codes, engine stumbling, CEL. In later stages multiple electrical faults simultaneously, ECU coated with oil - !! Recall — Camshaft Break (Production Defect 2015)
M270 engines with manufacturing date July–September 2015 have a defective weld seam on the camshaft lobe. Camshaft can break → engine damage. Recall with free replacement.
Symptoms: Sudden engine noise, power loss up to engine stall. Only vehicles with production date July–September 2015 affected - !! Electric Thermostat Failure from 90,000 km
The electrically-controlled thermostat on the M270 fails frequently and is difficult to access at the rear of the engine. Replacement costs 800–1,300 EUR at Mercedes workshops.
Symptoms: Engine does not reach operating temperature of 80°C, coolant temperature fluctuates, fault code P0128
+ 4 more engine weaknesses + vehicle weaknesses
Modular four-cylinder turbo of the first compact platform generation. Known for timing chain stretch and thermostat issues. Adequate power up to 156 hp.
- !! Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness from 90,000 km
The sealing ring on the camshaft adjuster solenoid fails. Oil creeps by capillary action through the wiring harness and destroys lambda sensors and the ECU. Repair €1,700–€4,000.
Symptoms: Lambda sensor fault codes, engine stumbling, CEL. In later stages multiple electrical faults simultaneously, ECU coated with oil - !! Recall — Camshaft Break (Production Defect 2015)
M270 engines with manufacturing date July–September 2015 have a defective weld seam on the camshaft lobe. Camshaft can break → engine damage. Recall with free replacement.
Symptoms: Sudden engine noise, power loss up to engine stall. Only vehicles with production date July–September 2015 affected - !! Electric Thermostat Failure from 90,000 km
The electrically-controlled thermostat on the M270 fails frequently and is difficult to access at the rear of the engine. Replacement costs 800–1,300 EUR at Mercedes workshops.
Symptoms: Engine does not reach operating temperature of 80°C, coolant temperature fluctuates, fault code P0128
+ 4 more engine weaknesses + vehicle weaknesses
Modular four-cylinder turbo of the first compact platform generation. Known for timing chain stretch and thermostat issues. Adequate power up to 156 hp.
- !! Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness from 90,000 km
The sealing ring on the camshaft adjuster solenoid fails. Oil creeps by capillary action through the wiring harness and destroys lambda sensors and the ECU. Repair €1,700–€4,000.
Symptoms: Lambda sensor fault codes, engine stumbling, CEL. In later stages multiple electrical faults simultaneously, ECU coated with oil - !! Recall — Camshaft Break (Production Defect 2015)
M270 engines with manufacturing date July–September 2015 have a defective weld seam on the camshaft lobe. Camshaft can break → engine damage. Recall with free replacement.
Symptoms: Sudden engine noise, power loss up to engine stall. Only vehicles with production date July–September 2015 affected - !! Electric Thermostat Failure from 90,000 km
The electrically-controlled thermostat on the M270 fails frequently and is difficult to access at the rear of the engine. Replacement costs 800–1,300 EUR at Mercedes workshops.
Symptoms: Engine does not reach operating temperature of 80°C, coolant temperature fluctuates, fault code P0128
+ 4 more engine weaknesses + vehicle weaknesses
More powerful 2.0L variant of the M270. Solid turbocharged four-cylinder with adequate performance. Oil consumption possible at high mileage.
- !! Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness from 90,000 km
A leaking camshaft adjuster solenoid allows oil to migrate into the wiring harness. Lambda sensors die first, then the engine ECU. Well-known failure pattern on all M270 variants.
Symptoms: Lambda fault codes, rough running, CEL. Oil smell in engine bay. In later stages multiple electrical faults - !! Recall — Camshaft Break (Production Defect 2015)
M270DE20 engines with manufacturing date July–September 2015: defective weld seam on the camshaft lobe leads to fracture and engine damage. Recall with free replacement.
Symptoms: Metallic noises from engine bay, power loss, in worst case engine stall - !! Electric Thermostat Failure from 90,000 km
Identical issue to the M270DE16: electrically-controlled thermostat at the rear of the engine fails prematurely. Difficult removal drives workshop costs to 700–1,300 EUR.
Symptoms: Engine runs permanently below operating temperature, coolant temperature fluctuations, fault code P0128
+ 4 more engine weaknesses + vehicle weaknesses
More powerful 2.0L variant of the M270. Solid turbocharged four-cylinder with adequate performance. Oil consumption possible at high mileage.
- !! Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness from 90,000 km
A leaking camshaft adjuster solenoid allows oil to migrate into the wiring harness. Lambda sensors die first, then the engine ECU. Well-known failure pattern on all M270 variants.
Symptoms: Lambda fault codes, rough running, CEL. Oil smell in engine bay. In later stages multiple electrical faults - !! Recall — Camshaft Break (Production Defect 2015)
M270DE20 engines with manufacturing date July–September 2015: defective weld seam on the camshaft lobe leads to fracture and engine damage. Recall with free replacement.
Symptoms: Metallic noises from engine bay, power loss, in worst case engine stall - !! Electric Thermostat Failure from 90,000 km
Identical issue to the M270DE16: electrically-controlled thermostat at the rear of the engine fails prematurely. Difficult removal drives workshop costs to 700–1,300 EUR.
Symptoms: Engine runs permanently below operating temperature, coolant temperature fluctuations, fault code P0128
+ 4 more engine weaknesses + vehicle weaknesses
World record holder at launch: the M133 was the world's most powerful production four-cylinder in 2013. 2.0 litres, 360 hp, 1.8 bar boost — absurd on paper, surprisingly reliable in practice. The well-known weakness is oil contamination of the turbo oil supply line on early vehicles (before Feb. 2014), which led to a recall. The 7G-DCT dual-clutch overheats under hard use in stop-and-go traffic. Keep to service intervals and treat the gearbox gently and you get a long-lived high-performance engine.
- !! Oil Feed Line Contamination / Turbo Damage from 30,000 km
Recall campaign for vehicles built before Feb. 2014: contaminated oil feed line to the turbo causes bearing wear and turbo damage. 365 affected vehicles.
Symptoms: Power loss, oil mist from exhaust, whistling from turbocharger, in extreme cases engine failure - !! 7G-DCT Dual Clutch — Judder and Clutch Damage from 60,000 km
The 7G-DCT dual-clutch gearbox frequently shows judder when pulling away on the M133 AMG. The clutch wears prematurely due to high torque spikes. Repair costs €3,500–€6,000.
Symptoms: Judder when pulling away and during gear changes (especially cold), slipping clutch feel, gearbox enters limp mode - !! Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness from 80,000 km
The M133 AMG shares the well-known Mercedes issue of leaking camshaft solenoids. Accelerated by higher engine temperatures in the AMG application.
Symptoms: Lambda sensor faults, rough idle, CEL. As it progresses, multiple electrical codes. Oil traces at camshaft solenoids
+ 6 more engine weaknesses + vehicle weaknesses
Vehicle Weaknesses
| Weakness | Cost | |
|---|---|---|
| 7G-DCT Dual Clutch Gearbox: Judder and Gear Change Noises 7G-DCT judders when pulling away and during shifts 1–3, especially during the cold warm-up phase. Software updates often help but do not always solve the problem permanently. Clutch wear increased in urban traffic. Symptoms: Juddering when pulling away, loud downshift noises, gearbox hunting for gears from 60,000 km | High |
Test Reports
TÜV Report 2024
The W176 is among the best compact cars in its age group at the MOT inspection and impresses with stable chassis technology.
2023-11ADAC Breakdown Statistics 2024
The W176 ranks among the most breakdown-free compact cars in its age group and consistently lands in the green zone.
2024-04Alternatives
Explore more
Known Problems and Issues +
A total of 51 weaknesses have been documented for the Mercedes-Benz A-Klasse W176 (2012–2018) — 40 engine-related and 11 vehicle-related. One problem engine: OM651DE22 (2.1L Diesel). Typical issues affect Gearbox, Electronics, HVAC, Other.
A-Klasse (OM607, 2012–2018) — Be Careful: Timing belt instead of chain -- maintenance obligation, Timing belt interference engine -- total loss risk, Injector failure K9K base. Power: 109–116 PS.
A-Klasse (OM651DE18, 2012–2018) — Be Careful: Piezo Injector Faults (220/250 CDI), Chain Tensioner Failure with Oil Loss, Particulate Filter Blockage with Short-Trip Use. Power: 136 PS.
A-Klasse (OM651DE22, 2012–2015) — Stay Away!: Chain Tensioner Seal Leaking — Recall, Timing Chain Stretch (Simplex Chain), Piezo Injector Faults. Power: 163–177 PS.
A-Klasse (OM607, 2013–2018) — Be Careful: Timing belt instead of chain -- maintenance obligation, Timing belt interference engine -- total loss risk, Injector failure K9K base. Power: 90–95 PS.
A-Klasse (OM651DE22, 2013–2018) — Stay Away!: Chain Tensioner Seal Leaking — Recall, Timing Chain Stretch (Simplex Chain), Piezo Injector Faults. Power: 136 PS.
A-Klasse (OM651DE22, 2015–2018) — Stay Away!: Chain Tensioner Seal Leaking — Recall, Timing Chain Stretch (Simplex Chain), Piezo Injector Faults. Power: 170–177 PS.
A-Klasse (M270DE16, 2012–2018) — Be Careful: Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness, Recall — Camshaft Break (Production Defect 2015), Electric Thermostat Failure. Power: 122 PS.
A-Klasse (M270DE16, 2012–2018) — Be Careful: Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness, Recall — Camshaft Break (Production Defect 2015), Electric Thermostat Failure. Power: 156 PS.
A-Klasse (M270DE20, 2012–2018) — Be Careful: Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness, Recall — Camshaft Break (Production Defect 2015), Electric Thermostat Failure. Power: 184–190 PS.
A-Klasse (M270DE20, 2012–2018) — Be Careful: Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness, Recall — Camshaft Break (Production Defect 2015), Electric Thermostat Failure. Power: 211–218 PS.
A-Klasse (M133, 2013–2015) — Be Careful: Oil Feed Line Contamination / Turbo Damage, 7G-DCT Dual Clutch — Judder and Clutch Damage, Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness. Power: 360 PS.
A-Klasse (M270DE16, 2015–2018) — Be Careful: Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness, Recall — Camshaft Break (Production Defect 2015), Electric Thermostat Failure. Power: 102 PS.
A-Klasse (M270DE20, 2015–2018) — Be Careful: Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness, Recall — Camshaft Break (Production Defect 2015), Electric Thermostat Failure. Power: 211–224 PS.
A-Klasse (M133, 2015–2018) — Be Careful: Oil Feed Line Contamination / Turbo Damage, 7G-DCT Dual Clutch — Judder and Clutch Damage, Camshaft Adjuster Solenoid Leaks — Oil in Wiring Harness. Power: 381–387 PS.
What to watch out for with the Mercedes-Benz A-Klasse? See the detailed listing of all engine and vehicle weaknesses in the sections above.
Frequently Asked Questions
What problems and weaknesses does the Mercedes-Benz A-Klasse W176 have? +
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Which Mercedes-Benz A-Klasse W176 engine is the most fun? +
Is the Mercedes-Benz A-Klasse W176 worth buying used? +
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Last updated: February 2026 · All information without guarantee