Mercedes-Benz A 180d W177 — Reliability
Reliability Summary
Best engine
K9K 1.5 dCi (post-2010) — 78/100
BUY
Worst engine
OM654 — 76/100
ACCEPTABLE
Average reliability
77/100
Engine Comparison
| Engine | Reliability Score | Verdict |
|---|---|---|
|
K9K 1.5 dCi (post-2010)
1.5L Diesel I4 |
78/100 | BUY |
|
OM654
OM654 2.0 Diesel I4 |
76/100 | ACCEPTABLE |
Engines in this model
BUY
78
K9K 1.5 dCi (post-2010)
1.5L Diesel I4
Euro 5/6 K9K (2010 on, 75-120 hp). The 90 and 110 hp versions are the ones mechanics recommend: the ...
View details →
ACCEPTABLE
76
OM654
OM654 2.0 Diesel I4
Mercedes-Benz's aluminium four-cylinder diesel from 2016 (OM654, 1.6-2.0 litres, 116-265 hp; OM654M ...
View details →Known Issues Across All Engines
| Issue | Engine | Severity |
|---|---|---|
| Con-rod bearing wear (rarer than pre-2010, not eliminated) | K9K 1.5 dCi (post-2010) | critical |
| Timing belt — INTERFERENCE ENGINE (critical) | K9K 1.5 dCi (post-2010) | high |
| Turbocharger wear at high mileage | K9K 1.5 dCi (post-2010) | moderate |
| EGR fouling + DPF (city use) | K9K 1.5 dCi (post-2010) | moderate |
| Injector wear | K9K 1.5 dCi (post-2010) | moderate |
| Roller rocker arm wear (engines built before mid-2018) | OM654 | high |
| Timing chain stretch (chain at the gearbox end) | OM654 | high |
| Coolant pump can leak into the vacuum system (recall, fire risk) | OM654 | moderate |
| Particulate filter and EGR clogging, oil diluted by diesel (short trips) | OM654 | moderate |
| Crankshaft out of specification (recall, engines built July-December 2020) | OM654 | minor |
| Oil leak at the front crankshaft seal (vibration damper) | OM654 | minor |
FAQ
Is the Mercedes-Benz A 180d reliable?
The Mercedes-Benz A 180d has 2 engine options with reliability scores ranging from 76/100 (ACCEPTABLE) to 78/100 (BUY). Average reliability: 77/100.
Which Mercedes-Benz A 180d engine is most reliable?
The K9K 1.5 dCi (post-2010) is the most reliable engine in the Mercedes-Benz A 180d, scoring 78/100 (BUY).
What problems does the Mercedes-Benz A 180d have?
Across all engine variants, the Mercedes-Benz A 180d has 11 known issues. The most common are related to Con-rod bearing wear (rarer than pre-2010, not eliminated), Timing belt — INTERFERENCE ENGINE (critical), Turbocharger wear at high mileage.