2024 Peugeot 508 Petrol · KW24 XKT

On 1.5 BlueHDi (DV5) and 2.0 BlueHDi (DW10) diesel engines, the integrated AdBlue SCR tank system is a frequent failure point. The internal dosing pump, heating element, or tank pressure sensors suffer electronic faults or urea crystallization, or the tank deforms. This triggers an amber UREA warning, emissions engine fault light, and an unyielding countdown preventing engine restart once the countdown reaches zero. Rectification typically demands replacing the entire sealed plastic tank assembly, as individual pump and sensor modules cannot be serviced separately.

The fastback coupe styling of the 508 Gen 2 uses frameless side glass that must automatically drop slightly when the door handle is pulled and rise into the weatherstrip upon closing. In freezing UK winter conditions, the glass frequently freezes solid against the rubber seals, causing the anti-pinch mechanism to trigger or damaging the electric window regulator cables and plastic clips. Over time, worn or dry window seals also lead to wind buffeting, high-speed cabin whistle, and damp ingress along the door cards.

On 1.2 PureTech petrol models, the engine uses a wet timing belt running directly submerged in hot engine oil. Using incorrect oil formulations, short urban trip fuel dilution, or age causes the belt's rubber compound to crack and shed fibrous debris. This dislodged debris collects in the oil sump and clogs the oil pump pickup strainer screen, causing oil starvation, brake vacuum pump loss of servo assistance, and eventual bottom-end engine seizure. Stellantis lowered the belt replacement interval and issued technical service actions.