Especially on early E90 335i (N54 engine) and some 2013–2014 F30 models, the HPFP is a known failure point. Should you buy a USED BMW 3 Series? - What goes WRONG?
Inspect around the valve cover gasket and oil filter housing with a flashlight. These are common leak points that can lead to more severe engine damage if neglected. buying a used bmw 3 series what to look for
Components like the water pump, thermostat, and plastic expansion tank often become brittle and fail around 80,000 to 100,000 miles. Look for white, chalky residue under the hood, which indicates dried coolant. Especially on early E90 335i (N54 engine) and