M Buyers Guide
Inspection checklist
X4 M40i F26, 2016 to 2018
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
- Water pump and thermostat failure about $1,000 to fix
Look for a water pump and thermostat replacement in the records and treat an original pump as due; check for coolant loss and watch the temperature on a long drive.
- Oil leaks at the valve cover and oil filter housing about $750 to fix
Look for oil residue around the top and front of the engine and underneath, sniff for burning oil after a drive, and ask whether either gasket has been replaced.
- VANOS solenoid faults about $680 to fix
Scan for camshaft timing fault codes and check for a rough or hunting idle once the engine is warm.
- Charge pipe cracking
Listen for a hiss under boost and check for a boost-related fault code, and ask whether the pipe has been replaced.
At the viewing
- A service history with oil changes on time.
- The water pump and thermostat replaced or budgeted for.
- No oil leaking from the valve cover or oil filter housing.
- No coolant loss or temperature warnings.
- A smooth idle with no misfire or camshaft timing codes.
- Proof the car has not been tuned (and on a tuned car, a stronger aftermarket charge pipe).
- Even wear on the staggered run-flat tires.
- A clean accident history.
Notes
From the X4 M40i F26 guide at M Buyers Guide. Repair costs are the guide's estimates, not quotes; the guide says where each comes from. Problems and costs as of the date printed.