BMW 4 Series2018

Known issues

• DPF (Diesel Particulate Filter) clogging and regeneration issues, especially on low-mileage or urban-driven examples
• Fuel injector stiction and carbon buildup on direct-injection engines, causing rough idle and reduced power
• Timing chain rattle on cold starts, particularly N47D20 variants, leading to potential tensioner failure
• Electrical gremlins including iDrive software glitches, window regulator failures, and battery drain issues
• EGR valve and cooler problems causing increased emissions and limp-mode activation
• Gearbox judder or hesitation on ZF 8-speed automatic (if equipped) during low-speed manoeuvres

Good for

• Excellent fuel economy (45–52 mpg combined WLTP on diesel variants) for motorway and commuter use
• Composed, refined driving dynamics and well-tuned suspension for comfort and handling balance
• Premium interior quality with intuitive infotainment and good build materials
• Strong resale value and wide availability of parts in the Irish and UK aftermarket