2012 Hyundai I40 1.7L Diesel · NV12 UCB

Manual i40s fail early on the clutch side: owner-fault analyses report clutch trouble well before normal wear, with a supplier change around 2014 blamed for a run of cars needing replacement at 40,000-60,000 miles, and RAC's own owners' survey records grinding when changing gears. PistonHeads owners describe exactly this car needing a clutch and flywheel job to fix hard-to-select ratios. The tell is a cold gearbox that fights reverse and first and a shudder through the pedal pulling away; on a £2,000 car a £500-£1,200 clutch and dual-mass flywheel bill is a genuine write-off risk.

Fault File's owner and MOT analysis of the i40 calls out DPF regeneration failure on the short-run CRDi cars: a check-engine light that clears for a few dozen miles then returns, limp-mode power loss and smoke on start-up, recurring even after fuel-pump or injector work because the small filter simply never reaches regeneration temperature on school-run duty cycles. Get Car Wise's guide puts fixing it anywhere from a cheap forced regeneration to a four-figure filter replacement, and removal is illegal for road use. UK buyers should assume any i40 diesel that has lived in town is carrying this bill unspent.