BMW 2 Series M235i Engine Replacement —Compare Prices &
Get Quotes

A reconditioned M235i (N55) engine typically costs £4,000–£8,500 supply only. Fitting adds £900–£2,000 depending on workshop location. Main dealer new engines can exceed £9,000 supply only. Used engines typically range from £2,500–£4,500. Use our calculator for a figure specific to your car.

The N55 is one of BMW's more reliable modern engines. It's far more robust than the twin-turbo N54 it replaced and doesn't suffer the timing chain issues of BMW's four-cylinder engines. However, it has known weak points: the plastic charge pipe is prone to cracking, wastegate rattle is common, and gaskets leak with age. With proper maintenance, these engines can exceed 150,000 miles.

Charge pipe failure (factory plastic unit cracks under boost), wastegate rattle (P30FF code, rattling on cold start and deceleration), oil leaks from valve cover and oil filter housing gaskets, and electric water pump failure (especially over 80,000 miles). Timing chain issues are less common on the N55 than on earlier BMW engines.

Apply the 70% BMW scrap threshold: if your M235i is worth £15,000 and a recon engine is £6,000 (40%), it's worth it. If the vehicle is a tired £8,000 example, the same engine exceeds 70% — get a scrap valuation first. The M235i's strong enthusiast following and retained value often justify replacement spend.

The engine code is listed on the VIN plate and vehicle documentation. The M235i (2014–2016) uses the N55B30O0 — a 3.0-litre turbocharged inline-six producing 322–326 bhp. Tell us your registration date and we'll confirm it for free.

The factory plastic charge pipe can be replaced with an OEM unit (£150–£400), but many owners upgrade to an aftermarket aluminium charge pipe (£300–£600) as a preventative measure. The aluminium unit will not crack under boost and is a worthwhile investment for any N55-powered car.

I have the Part 1 content for the M235i, which gives me all the data I need: the Step 0 results (Priority Medium, Assertive mode), the Era Map (only one row for N55B30O0 from 2014-2016), the engine codes, costs, and the specific reliability rating and sources mentioned in the Data Note. Now I need to draft Part 2. I'll structure it just like the other successful Part 2 responses. For Section 9, the Trust Points should reference the N55 engine's specific weak points from Part 1 (charge pipe, wastegate, oil leaks) and mention specialists' experience. The Final CTA should be price-anchored as usual. The Meta Title should follow the pattern "M235i Engine Replacement Cost UK — Compare Quotes" and stay within the character limit. The Production Note needs to state AggregateRating omitted, justify the price range source (Section 2), confirm Organization (not LocalBusiness) used, and confirm schema/content consistency (only N55B30O0 appears). Also need to confirm the Authority Model: the rating is newly assigned based on the 6 sources listed in Part 1's Data Note. I should mirror the structure and phrasing from the most recent, detailed Part 2 responses, like the one for the Range Rover Sport P510e or the BMW 120d. The tone should be professional and precise, matching the brand voice (BMW Precision & Engineering) and the guidelines.