Common Problems with the
2017 Peugeot 308 (T9)

The 1.2 PureTech three-cylinder petrol engine utilises a wet timing belt operating submerged in engine oil. Fuel contamination and thermal stress cause belt rubber to degrade, shedding fibrous particles into the engine sump. These particles block the oil pump strainer, causing severe oil starvation, vacuum pump failure, and loss of assisted braking (UK recall R/2020/331), with catastrophic engine failure if unaddressed.

BlueHDi diesel engines (1.6 and 1.5 variants) utilize an integrated AdBlue tank assembly housing the urea delivery pump, heater, and level sensor. Urea crystallisation and circuit board failure cause delivery failure, illuminating the UREA warning lamp and initiating a non-restart countdown (commencing at 700 miles). Because the tank is a factory-sealed unit, replacement of the complete tank is required.

The 1.5-litre BlueHDi (DV5R) 16-valve engine introduced in late 2017 uses a 7mm chain connecting the twin overhead camshafts. The chain is prone to excessive wear and stretching, producing metallic rattle before snapping suddenly. Chain failure bends valves, cracks camshaft carriers, and destroys the cylinder head. Stellantis introduced an 8mm upgraded chain kit and revised cylinder head housing to resolve the defect.

The central 9.7-inch touchscreen controls navigation, radio, and all ventilation and heater settings. On early SMEG and later NAC units, internal memory corruption and software bugs cause freezing, black screens, sluggish response, and random reboots. When the screen freezes, occupants cannot adjust cabin heating, fan speeds, or windscreen demisting.

On 2013–2018 T9 models, the hollow rear torsion beam axle can develop internal stress clicks or creaks over uneven surfaces and road camber changes. The metallic creaking originates from internal axle welding and damping voids. Peugeot issued technical service bulletins advising technicians to inject expanding structural polyurethane foam into the beam or replace the axle.

The EMP2 platform front suspension utilizes rubber lower control arm rear bushes and anti-roll bar drop links that wear quickly when subjected to speed humps and potholed UK roads. Perished rubber bushes cause steering wander, knocking over bumps, and accelerated uneven tyre shoulder wear, frequently resulting in UK MOT test advisories or failures.