Inspection checklist

Before you go

• Open recalls. Run the VIN through NHTSA or a BMW dealer and ask for proof every recall was done.
• History report. Check the title, accidents, owners and mileage record.
• Service records. Ask for them in advance, ideally from a BMW dealer or specialist.
• Independent inspection. Book a pre-purchase inspection with a shop that knows this engine.

Known problems on this car

• Charge pipe failure about $300 to fix

  Look for an aftermarket aluminum charge pipe, or ask whether the original has failed or been replaced.

• Carbon buildup about $500 to fix

  Ask about mileage and whether walnut blasting has been done; budget for it as the car accumulates miles.

• Cooling system / water pump about $1,500 to fix

  Check service records for water pump and thermostat work, and watch for temperature irregularities.

• Rear differential mount knock about $600 to fix

  Listen for a knock from the rear when getting on and off the throttle at low speed, and ask whether the updated differential mount has been fitted.

• Crank hub slippage 2019 to 2021 cars about $4,000 to fix

  Confirm whether the car is the N55 OG or the S55 Competition/CS. On S55 cars ask about tune history and whether a pinned or upgraded crank hub has been fitted.

• Fuel tank leak 2016 cars about $2,000 to fix

  Look under the car on the driver's side for wet fuel or staining, sniff for fuel after a fill-up, and scan for fuel tank leak codes. A BMW dealer can confirm by VIN whether the 15-year cover applies.

At the viewing

First determine N55 (OG) vs S55 (Competition/CS), since that changes both value and the issue checklist. Full service history, tune clarity on S55 cars, crank hub status on tuned S55s, manual gearbox for collectibility, and desirable colors. The CS is a special-edition value anchor. Check by VIN that recalls are done: instrument panel software on 2018 cars (17V-719), knee air bags on 2019 and 2020 cars (19V-352) and seat belts on 2021 cars (21V-554). On a 2016 car, look for wet fuel under the driver's side, where the tank's welded top plate can leak; BMW covers it for 15 years (SI B01 03 22).