2020 BMW M340I engine problems

38 owner complaints filed with NHTSA name the engine on the 2020 BMW M340I — 72% of all complaints for this model year.

Engine complaints

72%

share of all complaints

—

median reported incident mileage

0 / 0

crash / fire reports

What owners report

“I am reporting a safety concern involving BMW vehicles equipped with the B58 Technical Update (B58TU) engine, commonly found in model years 2019–2021. These vehicles utilize a variable-displacement engine oil pump containing an internal thermoplastic adjusting component responsible for regulating…”
filed Sep 13, 2026
“Oil pump for the 2020 model is made with plastic internals. The passage that controls the flow of oil into your engine is made of plastic. The car didn’t even have 40,000 miles and the plastic broke causing the passage to be in a very close to shut position not allowing enough oil to enter the…”
filed Sep 1, 2026
“I am reporting a premature oil pump failure on my 2020 BMW M340i xDrive with 42 thousand miles. The vehicle has been well maintained and has not experienced any oil pressure warning lights. However, the electronic engine oil level measurement repeatedly fails to complete once the engine is fully warmed up. I have also…”
filed Aug 13, 2026

Verbatim excerpts from complaints filed with NHTSA. Reports are not independently verified.

?A software error may cause an unwanted pressure pulsation in the transmission during a "Remote Engine Start."
B240323 · Service Bulletin/Repair Instructions · issued Aug 1, 2023