Mercedes-Benz GLA 180 d
Renault-based small diesel (K9K). Economical but with little power reserve. Prone to EGR fouling and DPF issues under pure short-trip use.
Economical SUV
80 kW diesel and DCT in the GLA: low running costs as the only plus point. Driving pleasure is not the aim here.
Engine Weaknesses 6
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
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
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
With predominantly short-trip use, the injectors on the OM607 coke prematurely. Cleaning additives can delay this; replacement costs 800-1,500 EUR.
Symptoms: Rough engine running, power loss, increased consumption, black smoke on acceleration
The EGR valve on the OM607 is prone to carbon deposits with typical urban driving. On the A/B 180d with frequent short-trip use, this is one of the most commonly cited weak points.
Symptoms: Engine warning light, power loss at mid-range rpm, limp mode, fault code P0400/P0401
The 1.5-litre diesel OM607 is primarily designed for long-distance use. With predominantly urban driving and short trips under 10 km, the DPF cannot reach operating temperature for a complete regeneration.
Symptoms: DPF warning symbol, frequent prompts for motorway driving for regeneration, rising oil level through fuel dilution
Vehicle Weaknesses 7
On GLA X156 build years 2016–2018 the eCall emergency system could malfunction when Mercedes me services were active in transport mode. Automatic and manual emergency calls were not transmitted correctly. Fixed via OTA software update.
MOT reports cite brake lines and parking brake as typical weak points on the GLA X156. Brake lines are prone to corrosion.
The 7G-DCT in the GLA X156 shows jerky gear changes from 2nd to 3rd gear in heavy city use from approx. 60,000 km. Worn clutch plates (under 1.8 mm) are a common cause; a gearbox oil change can ease symptoms.
In cold weather the electric door mirrors on the GLA X156 often fail to fold in. The optional sunroof does not fully open or close at low temperatures. Cause is cold sensitivity of the drive motors and control units.
At motorway speeds above 120 km/h distinct wind noise is reported in the area of the door seals and bonnet. The bonnet vibrates measurably, indicating insufficient body sealing.
Many GLA X156 owners report annoying wind noise at higher speeds from around 120 km/h. The bonnet also vibrates at higher speed.
Owners report creaking and rattling noises from the interior. Seat belt guides and seats rattle frequently. Typical at higher mileages.
Reports & Tests
1 owner complaints filed with NHTSA (2013–2020). Most reported: Lane Departure (1).