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The BMW 420 is the most popular engine option for the BMW 4 Series. It features a 2.0-litre petrol or diesel engine to offer a compelling mix of performance and efficiency in a sporty, coupé-like body style.
AA finance available
London
London
London
London
London
London
AA finance available
Ruislip
AA finance available
Dunstable
Bedford
Consider a pre-purchase vehicle inspection. An independent AA mechanic will check for any issues, helping you avoid costly surprises.
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West Drayton
AA finance available
Ruislip
Brentwood
Maidstone
AA finance available
Dunstable
AA finance available
Dunstable
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Borehamwood
AA finance available
Rainham
Orpington
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Overall rating 5/5The 420 is an engine designation within the 4 Series and is available in Coupé, Gran Coupé, and Convertible body styles. For the diesel, the 420d uses a 2.0-litre four-cylinder turbo diesel engine that develops around 190hp with 400Nm of peak torque. Meanwhile, the 420i petrol uses a 2.0-litre four-cylinder turbo petrol engine that develops 184hp and 300Nm of torque. If you do a lot of miles, the 420d is the better option, but having said that, you can’t really go wrong with the 420i either.