BMW 4 Series 418i Engine ReplacementCompare Prices & Get Quotes

A BMW 4 Series 418i 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 B38B15A with warranty. Supply-only prices exclude fitting - budget an additional £500-£900 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 new components

The most common early warning sign is a metallic rattling noise from the engine, especially during cold starts. As the problem worsens, you may notice 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 disappear as oil pressure builds
• 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 418i valued at £6,000-£14,000, 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 (£1,500-£2,200) 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 418i engine replacement takes 1-2 days for a specialist workshop, assuming the replacement engine is already available. The B38 is a relatively compact three-cylinder unit, making access simpler than larger BMW engines.

• Supply: 1-2 days for delivery from stock
• Fitting: 8-12 hours of workshop time
• Allow 2-3 days total for a supply-and-fit service

The BMW 418i uses a 1.5-litre three-cylinder B38B15A engine producing 136hp, while the 420i uses a 2.0-litre four-cylinder B48 engine producing 184hp. The 420i offers significantly more power and refinement, but the 418i delivers better fuel economy and lower running costs. Both engines share BMW's TwinPower Turbo technology.

• 418i: 1.5L 3-cyl, 136hp, better fuel economy
• 420i: 2.0L 4-cyl, 184hp, more power and smoother
• Engine codes are not interchangeable - always match the correct code

Yes - every rebuilt and reconditioned BMW 4 Series 418i 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