AI DamageBMW M340I: problems, complaints, bulletins
Summary for the BMW M340I across 6 model years: 73 owner complaints and 259 NHTSA service bulletins, plus repair videos. Pick a year for details.
Model years
What fails most often
- 1 Engine 66% of all complaints
- 2 Electrical system 12% of all complaints
- 3 Powertrain 8% of all complaints
- 4 Engine and cooling 5% of all complaints
- 5 Fuel/propulsion system 5% of all complaints
- 6 Steering 4% of all complaints
- 7 Service brakes 4% of all complaints
- 8 Tires 3% of all complaints
- Engine: 48 complaints (66% of all); manufacturer bulletins for this component: 16.
- Electrical system: 9 complaints (12% of all); manufacturer bulletins for this component: 246.
- Powertrain: 6 complaints (8% of all); manufacturer bulletins for this component: 27.
- Engine and cooling: 4 complaints (5% of all); manufacturer bulletins for this component: 50.
- Fuel/propulsion system: 4 complaints (5% of all).
Engines and transmissions
US-market versions per EPA. On the right: how many NHTSA complaints name this engine or transmission type.
- 3 L · petrol · turbo · 6 cyl 2020
- 3 L · hybrid · turbo · 6 cyl 2021
- automatic, 8-speed 2020–2021
Drive: RWD, AWD
Symptoms owners describe
How many of the 73 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Engine | 48 | 0 | 16 |
| Electrical system | 9 | 0 | 246 |
| Powertrain | 6 | 0 | 27 |
| Engine and cooling | 4 | 0 | 50 |
| Fuel/propulsion system | 4 | 0 | 0 |
| Steering | 3 | 0 | 23 |
| Service brakes | 3 | 0 | 17 |
| Tires | 2 | 0 | 12 |
| Wheels | 2 | 0 | 9 |
| Suspension | 2 | 0 | 8 |
| Air bags | 1 | 0 | 8 |
| Equipment | 0 | 0 | 197 |
| Structure | 0 | 0 | 55 |
| Visibility | 0 | 0 | 36 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
I was driving and going to pickup something from the store localy around like 8 pm, and suddenly my car's wheels stopped responding, and the sign's came up on the car of something like "impaired driving" , and the car was telling me to pull over, i was nearby walmart and i pulled into the parking lot slowly, and could…
There were no warnings, no lights on the dash, no check engine and no codes on the car or when read with a diagnostic scanner. I even included the difference between the 2020 oil pump (plastic) to the 2021 and up oil pump (metal) which was bought from BMW Parts in Mamaroneck.
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.
This creates a severe safety hazard, as the vehicle can experience a sudden loss of motive power or complete engine seizure while travelling at highway speeds, placing the occupants and surrounding traffic at immediate risk of a collision.Furthermore, a known software bug or sensor interference tied to this specific…
The issue is a fire risk and a very expensive repair that should be covered by the manufacturer due to a known defect.
The BMW B58TU oil pump thermoplastic component issue that can cause catastrophic failure to the engine. The the gen 1 oil pump was made from plastic and after issues were discovered, they switched to metal oil pumps.
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
What to check before buying
- Engine. Cold start, unusual noises, oil leaks and engine codes.
- Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.
- Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.
- Engine and cooling. Radiator and fan after a frontal hit, coolant level and condition, overheating.
Manufacturer service bulletins
Bulletin titles as filed with NHTSA.
- The Radiator Grilles Lower Active Air Flap Assembly limited warranty for defects in materials and/or…
- The Supplemental Restraint Systems (SRS) Front Passenger’s Seat Occupancy Capacitive Interior Sensor (CIS)…
- An interference noise (groaning noise) can be heard from within the heating and air-conditioning unit in…
- The electrical system of BMW vehicles has been subject to an ongoing development process over the last few…
- At low outside temperatures (below 40 degrees F) and slow driving speeds (i.e
- Functional noises (squealing/honking) when braking shortly before the vehicle comes to a stop
- BMW AG has requested the inspection of all dealer stock of the following part number(s) listed below to…
- ?A software error may cause an unwanted pressure pulsation in the transmission during a "Remote Engine Start."
- The left front suspension's aluminum strut dome (general area circled) was incorrectly riveted to the…
- Headlight check control (CC) message 128 "High beam headlight failure" is displayed
- Condensation is present on the inner surfaces in one or both taillights (circled)
- A limited number of the G20 PHEVs may not have been supplied with an Occasional Use Charging (Standard…
Repair videos
We do not copy videos: these are YouTube links credited to their authors. Amounts are as stated by the author and not verified by us.
- 2020 BMW M340I G20 XDRIVE REBUILD PART 2 REMOVING PARTS
- BROUGHT A CHEAP 2020 BMW G20 M340I XDRIVE DAMAGED! REBUILD PROJECT. COPART UK
- 2020 BMW M340I G20 XDRIVE COPART REBUILD PART 3
- 2020 BMW M340I G20 XDRIVE COPART REBUILD PART 5
- 2020 BMW M340I G20 XDRIVE COPART REBUILD PART 4
- Rebuilding My BMW M340I - Almost Back On The Road
Other models of this make
Read also
Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-04.