BMW 4 Series 428i Engine ReplacementCompare Prices & Get Quotes

A BMW 4 Series 428i engine replacement typically costs £1,200-£2,200 for a used unit, £2,200-£3,800 for a reconditioned engine, and £2,800-£4,500 for a fully rebuilt N20B20A with warranty. Supply-only prices exclude fitting - budget an additional £600-£1,000 for specialist labour.

• Used engine: cheapest option, variable mileage and condition
• Reconditioned: tested and restored to good working order
• Rebuilt: fully stripped, inspected, and built to factory specification with upgraded timing components

The most common early warning sign is a rattling or clacking noise from the front of the engine on start-up. As the problem worsens, you may notice a rattling or slapping noise during acceleration, poor engine performance, a check engine light, or in severe cases, the engine may fail to start or suffer catastrophic damage.

• Rattling noise on cold start that may last several seconds
• Engine running rough or loss of power
• Check engine light with timing-related fault codes

It depends on the car's value and condition. With a typical 428i valued at £6,000-£16,000, a rebuilt engine at £2,800-£4,500 represents a significant but often justifiable investment - especially if the car is otherwise in good condition. For cars at the lower end of the value range, a timing chain repair (£1,800-£2,800) may be the more sensible option.

• Vehicle worth over £10,000: replacement usually makes financial sense
• Vehicle worth under £6,000: evaluate carefully; repair may be better value
• Always get a specialist diagnosis before deciding

A typical BMW 4 Series 428i engine replacement takes 1-2 days for a specialist workshop, assuming the replacement engine is already available. The N20 is a well-understood engine with good parts availability.

• Supply: 1-2 days for delivery from stock
• Fitting: 10-14 hours of workshop time
• Allow 2-3 days total for a supply-and-fit service

The BMW 428i uses the N20B20A 2.0-litre four-cylinder turbo petrol engine producing 245hp, while the 430i (introduced in 2016) uses the newer B48B20B 2.0-litre four-cylinder engine producing 252hp. The B48 is a more modern design with improved reliability and fewer timing chain issues, but the N20 remains a capable and enjoyable engine when properly maintained.

• 428i: N20 2.0L 4-cyl, 245hp, produced 2013-2016
• 430i: B48 2.0L 4-cyl, 252hp, produced 2016 onwards
• Engine codes are not interchangeable - always match the correct code

Yes - every rebuilt and reconditioned BMW 4 Series 428i engine supplied through EnginesMarket comes with a minimum 12-month unlimited-mileage warranty. Used engines typically carry a shorter warranty (30-90 days), so always confirm the terms with your chosen supplier.

• Rebuilt/reconditioned: 12-month warranty minimum
• Used: typically 30-90 days depending on supplier
• Always request warranty terms in writing before purchase