Bmw M340I problems and owner complaints
Explore the records behind recurring owner reports.
Key facts
69 owner complaints analyzed
14 distinct recall campaigns
21,581 mi median reported failure mileage
Scope: 2019 to 2023 model years. Data snapshot: . 8 complaints include usable failure mileage.
Most common problems
Engine is the most frequently named component, appearing in 45 of 69 complaints (65.2%). A complaint can name multiple components.
| Topic | Matching reports | Share of complaints |
|---|---|---|
| Electrical and battery issues | 7 | 10.1% |
| Steering behavior | 6 | 8.7% |
| Braking behavior | 5 | 7.2% |
| Engine operation | 4 | 5.8% |
| Transmission and shifting | 1 | 1.4% |
| Fuel system concerns | 1 | 1.4% |
Topic matches use published keyword rules. They describe mentions, including negations or comparisons, and do not confirm a diagnosis. Read the matching rules.
Component breakdown
Number of unique complaints naming each component. Top eight shown.
| Category | Count |
|---|---|
| Engine | 45 |
| Unknown Or Other | 10 |
| Electrical System | 9 |
| Power Train | 5 |
| Fuel/Propulsion System | 4 |
| Engine And Engine Cooling | 3 |
| Service Brakes | 3 |
| Steering | 2 |
Engine: 45; Unknown Or Other: 10; Electrical System: 9; Power Train: 5; Fuel/Propulsion System: 4; Engine And Engine Cooling: 3; Service Brakes: 3; Steering: 2
Reported problems by failure mileage
Complaint counts in mileage bands. These are not failure rates per vehicle or mile.
| Category | Count |
|---|---|
| Under 25,000 | 4 |
| 25,000 to 49,999 | 2 |
| 50,000 to 74,999 | 1 |
| 75,000 to 99,999 | 1 |
| 100,000 to 149,999 | 0 |
| 150,000 and above | 0 |
Under 25,000: 4; 25,000 to 49,999: 2; 50,000 to 74,999: 1; 75,000 to 99,999: 1; 100,000 to 149,999: 0; 150,000 and above: 0
Under 25,000 miles has the most reports with usable mileage (4). 61 complaints have missing, zero or invalid mileage.
Complaints over time
Year the complaint was filed, not the vehicle model year or incident year. The snapshot year is partial.
| Category | Count |
|---|---|
| 2020 | 3 |
| 2021 | 1 |
| 2022 | 2 |
| 2023 | 12 |
| 2024 | 8 |
| 2025 | 15 |
| 2026 | 28 |
2020: 3; 2021: 1; 2022: 2; 2023: 12; 2024: 8; 2025: 15; 2026: 28
Pattern summary
Engine leads the component reports. Electrical and battery issues appears in 7 complaint narratives. Steering behavior appears in 6 complaint narratives. Braking behavior appears in 5 complaint narratives. Use these patterns to inspect individual reports and prepare questions for a mechanic.
Calculated from recorded counts. An AI narrative has not been published for this selection.
Complaint evidence
Examples provide context, not a representative sample or a verified diagnosis.
Owner report 11611038 · 2024-08-26 (August 26, 2024)
Starter went bad which lead to shortage within the lithium ion battery and regular battery. Car came to a stop and did not move in an intersection, blocking both lanes of traffic. Furthermore, car could not be put into neutral as it could not be started. There was smoke emanating from the engine on further restart attempts. Car had to be towed where it was determine this was the problem. Warning message during re-start "engine overheated" though temperate guage suggested it was still cold.
Owner-reported narrative. Look up ODI 11611038 at NHTSA ↗
Owner report 11631042 · 2024-12-16 (December 16, 2024)
The starter malfunctioned causing electrical damage to the motor and related components. Although there is literature that exists that this is a potential problem for this vehichle, BMW refuses to fix the problem and is asking me to pay. My warranty is expired by 4 months, but I have only 37,800 miles. The fact that there are 105K vehicles with this potential problem is evidence that this problem exists. They should be paying for what is an obvious manufacturer defect.
Owner-reported narrative. Look up ODI 11631042 at NHTSA ↗
Owner report 11521806 · 2023-05-13 (May 13, 2023)
Oil measurement fails at 20%, unable to tell how much oil is in engine, can lead to severe engine damage where the engine seizes and you loose power brakes and steering. Dealer says only fix is oil pump replacement.
Owner-reported narrative. Look up ODI 11521806 at NHTSA ↗
Owner report 11730475 · 2026-04-10 (April 10, 2026)
Safety Hazard: Oil Pump Failure Leading to Sudden Engine Stall (BMW B58TU engines) Description of Defect: The oil pump module in the 2020 BMW M340i (G20) contains internal plastic components that are prone to thermal degradation and premature failure. These plastic parts can crack or disintegrate, causing a sudden loss of oil pressure. Increasing wear on internal engine components and even leading to irreversible engine damage. Safety Risk: A failure of the oil pump leads to insufficient lubrication of critical engine components, which can r…
Owner-reported narrative. Look up ODI 11730475 at NHTSA ↗
Owner report 11655346 · 2025-04-18 (April 18, 2025)
I cruised on a city street at the speed limit. The light turned red and I came to a full stop. The start/stop system was activated and the engine “stopped” to conserve power while my foot was on the brake. The light turned green and I took my foot off the brake, the engine failed to start and did not start with countless attempts. Digital cluster and CarPlay proceeded to work, exterior lights work. Called a tow to the nearest BMW dealership for assistance.
Owner-reported narrative. Look up ODI 11655346 at NHTSA ↗
Owner report 11686855 · 2025-09-12 (September 12, 2025)
The contact owns a 2020 BMW M340I. The contact stated that while merging onto the highway and accelerating, there was an abnormally loud banging sound coming from the vehicle before the vehicle stalled. The contact was able to coast forward. There were no warning lights illuminated. The contact removed the panels, and there was metal falling out. The contact stated that there was a sizable hole in the engine, and metal was showing from the cam plate and oil pump. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The…
Owner-reported narrative. 59,015 miles reported. Look up ODI 11686855 at NHTSA ↗
Owner report 11491782 · 2022-11-01 (November 1, 2022)
The contact owns a 2021 BMW M340I. The contact stated while driving various speeds, the vehicle independently shifted from reverse(R) to drive(D) to park(P). The contact stated that while driving approximately 10 MPH and attempting to stop the vehicle, the brake pedal was depressed and went to the floorboard. The contact stated that the brake failed to operate as designed. The vehicle was towed to a dealer who diagnosed that the vacuum pump needed to be replaced. The vehicle was repaired. The contact stated that an unknown transmission repair w…
Owner-reported narrative. 4,000 miles reported. Look up ODI 11491782 at NHTSA ↗
Owner report 11658972 · 2025-05-05 (May 5, 2025)
My vehicle doesn’t read the oil level since the fuel pump that BMW used to manufacture the car is made out of plastic material. There has been hundred of complaints about the same issue with the oil pump not working properly due to the fact that BMW used plastic instead of metal etc. I would like for the NHTSA to take a look at this issue and please consider making it a recall for the users that are having this “Oil Pump” issue please thank you.
Owner-reported narrative. Look up ODI 11658972 at NHTSA ↗
Recalls by model year
All campaigns in the snapshot affecting each model year, including recalls announced years later.
Recall campaigns
Shared campaigns appear once in each affected model year.
| Category | Count |
|---|---|
| 2019 | 5 |
| 2020 | 10 |
| 2021 | 6 |
| 2022 | 1 |
| 2023 | 1 |
2019: 5; 2020: 10; 2021: 6; 2022: 1; 2023: 1