2019-2025 BMW M340i Problems: 11 Issues Every Owner Should Know

2019-2025 BMW M340i Problems: 11 Issues Every Owner Should Know | Au7o

NHTSA Recalls7 recalls

SEAT BELTS

BMW of North America, LLC (BMW) is recalling certain 2019-2022 330i, 330i xDrive, M340i, 2022 430i Coupe, 2021-2022 430i, M440i Convertible, and 2020-2022 228i xDrive Gran Coupe vehicles. The receiver audio module control unit software may fail to properly generate audible seat belt warnings to the driver to fasten their seat belt. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."

Campaign #23V58400016/08/2023

ELECTRICAL SYSTEM:BODY CONTROL MODULE:SOFTWARE

BMW of North America, LLC (BMW) is recalling certain 2023 330i, 330i xDrive, M340i, M340i xDrive, M3, 330e, 330e xDrive, 430i Convertible, 430i xDrive, M440i, 2022-2023 430i, 430i xDrive, M440i xDrive, i4 eDrive40, and i4 M50 vehicles. During a service visit, a replacement electronic control unit (ECU) may have been installed with incorrect programming, which can cause the automatic door locking (ADL) function to not lock the doors as intended.

Campaign #23V11800023/02/2023

SEAT BELTS

BMW of North America, LLC (BMW) is recalling certain 2021 2 Series (230i, 230i xDrive, M240i, M240i xDrive), 330e, 330e Xdrive, 4 Series Coupe (430i, 430i xDrive, M440i xDrive) M4 Coupe, M4 Competition Coupe, BMW 4 Series Convertible (430i, M440i), BMW X1 sDrive28i, xDrive28i, 2 Series Gran Coupe (228i, 228i xDrive, M235i xDrive), M2 Competition Coupe, 330i, 330i xDrive, M340i, M340i xDrive, M3, M3 Competition, 530i, 530i xDrive, 540i, 540i xDrive, MINI Hardtop 2 Door (Cooper, CooperS, JCW), X2 sDrive28i, X2 xDrive28i, X2 M35i, Z4 sDrive30i, Z4 M40i, MINI Hardtop 2 Door (Cooper SE), MINI Convertible (Cooper, Cooper S, JCW), MINI Clubman (Cooper S, Cooper S All4, JCW), MINI Countryman (Cooper, Cooper All4, Cooper S, Cooper S All4, JCW All4), Rolls Royce Ghost, MINI Countryman (Cooper S E All4), Rolls Royce Phantom, Rolls Royce Cullinan, and Toyota Supra vehicles. The passenger seat belt Automatic Locking Retractor (ALR) may deactivate early, before the webbing fully retracts. As such, these assemblies fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 208, "Occupant Crash Protection."

Campaign #21V55400021/07/2021

ELECTRICAL SYSTEM:12V/24V/48V BATTERY

BMW of North America, LLC (BMW) is recalling certain 2021 M340i xDrive, M440i xDrive Coupe, 530i, 530i xDrive, 540i, 540i xDrive, 740Li, 740Li xDrive, 840i Gran Coupe, 840i xDrive Gran Coupe, X5 sDrive40i, X5 xDrive40i, X6 sDrive40i, X6 xDrive40i, and X7 xDrive40i vehicles. The connection between the 48-Volt battery and the starter-generator may not have been assembled properly, which can cause increased electrical resistance at the connections.

Campaign #20V76100009/12/2020

BACK OVER PREVENTION: SENSING SYSTEM: CAMERA

BMW of North America, LLC (BMW) is recalling certain 2019-2021 X3 sDrive30i, X3 xDrive30i, X3 M40i, X3M, X4 xDrive30i, X4 M40i, M550i, X4M, X5 sDrive40i, X5 xDrive40i, X5 xDrive50i, X5M, X5 M50i, X7 xDrive40i, X7 xDrive50i, X7 M50i, Alpina XB7, 330i, 330i xDrive, M340i, M340i xDrive, and 8 Series Coupe, Convertible and Grand Coupe, 840i, 840i xDrive, M850i xDrive, M8, 2020-2021 530e, 530e xDrive, 330e, 330e xDrive, 745Le, 745Le xDrive, X5 xDrive45e, X3 xDrive30e, X6 sDrive40i, X6 xDrive40i, X6 xDrive50i, X6 M50i, X6M, 530i, 530i xDrive, 540i, 540i xDrive, M550i xDrive, M5, 740i, 740Li, 740Li xDrive, M760i Drive, M760Li xDrive, 750Li xDrive Alpina, Alpina B7 xDrive, and 2021 4 Series Coupe 430i, 430i xDrive, M440i xDrive vehicles. When shifting into Reverse, a small portion of the rearview image may be obscured, or the screen may not illuminate. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard (FMVSS) number 111, "Rear Visibility."

Campaign #21V09600019/02/2021

+ 2 more recalls. Check all on NHTSA.gov

Enter your VIN at NHTSA.gov to check recalls specific to your vehicle.

Frequently Asked Questions

What are the most common BMW M340i problems?

According to Au7o's analysis of 1,250+ owner reports, the 2019-2025 BMW M340i has 11 documented issues. The most frequently reported are: Coolant Loss from Expansion Tank and Water Pump, High-Pressure Fuel Pump (HPFP) Failure, Loss of Brake Assist from Brake Vacuum Pump Damage (Recall 21V-598). Of these, 3 are rated critical and should be addressed promptly.

Is the BMW M340i reliable?

The 2019-2025 BMW M340i has 11 known issues documented across 1,250+ owner reports. 3 issues are rated critical: Coolant Loss from Expansion Tank and Water Pump and High-Pressure Fuel Pump (HPFP) Failure and Loss of Brake Assist from Brake Vacuum Pump Damage (Recall 21V-598). Prospective buyers should inspect for these issues and factor potential repair costs into their purchase decision. Regular maintenance following the manufacturer's schedule helps prevent many common problems.

How much does it cost to fix common BMW M340i problems?

Repair costs for known BMW M340i issues range from $0 to $2,500, depending on the specific problem and whether you choose DIY or professional repair. The most critical issue, Coolant Loss from Expansion Tank and Water Pump, typically costs $400-$1,200 to repair. Au7o provides step-by-step DIY maintenance guides that can help reduce repair costs.

What year BMW M340i is the most reliable?

Reliability varies across model years of the BMW M340i. Based on documented issues, problems are most commonly reported in earlier model years. Au7o recommends checking the specific known issues for your target year before purchasing, and having a pre-purchase inspection performed by a qualified mechanic. Our known issues database covers the 2019-2025 BMW M340i with 11 documented issues documented across 1,250+ owner reports.

What is the 2020-2024 BMW M340i Coolant Loss from Expansion Tank and Water Pump?

The M340i's B58 engine experiences the same coolant loss issues as other B58-powered BMWs, but the M340i's higher sustained performance driving tends to accelerate the problem. The plastic coolant expansion tank develops hairline cracks from heat cycling, and the electric water p… Repairs typically run $400-$1,200. Severity: high.

What is the 2020-2024 BMW M340i High-Pressure Fuel Pump (HPFP) Failure?

The B58 engine's high-pressure fuel pump can fail, though at lower rates than the older N54 engine. When the HPFP fails, fuel pressure drops below the minimum required for proper direct injection, causing long cranking, rough idle, misfires, and in severe cases, the engine stalli… Repairs typically run $600-$1,500. Severity: high.

What is the 2020 BMW M340i Loss of Brake Assist from Brake Vacuum Pump Damage (Recall 21V-598)?

Faulty engine management software (DME) can command the combined oil/vacuum pump that supplies vacuum for power brake boost in a way that damages it under certain engine-start conditions — for example pressing the start/stop button twice in quick succession, or tapping the brake… Repairs typically run $0-$0. Severity: high.

What is the 2020-2024 BMW M340i Intake Valve Carbon Buildup?

As a direct-injection engine, the B58 in the M340i does not have fuel washing over the intake valves, leading to gradual carbon deposit buildup on the valve backs. Oil vapors from the crankcase ventilation system deposit carbon that restricts airflow and reduces performance. Symp… Repairs typically run $400-$800. Severity: medium.

What is the 2020-2024 BMW M340i Oil Filter Disintegration in Housing?

The B58 engine has a documented tendency for paper oil filters to shred and break apart during normal use. As oil passes through the filter under pressure, the filter media can separate from the end caps and tear into multiple pieces. Shredded filter material can deposit paper fr… Repairs typically run $50-$200. Severity: medium.

What is the 2019-2025 BMW M340i ZF 8HP Harsh / Jerky Low-Speed Shifting and Mechatronic Faults?

Owners report harsh or jerky shifts from the ZF 8-speed automatic, most noticeable on the 1-2 and 2-3 changes at low speed before the drivetrain is warmed up, and aggravated by Sport mode in cold stop-and-go traffic. The ZF 8HP is sensitive to fluid condition; degraded or low flu… Repairs typically run $350-$2,500. Severity: medium.

What is the 2019-2025 BMW M340i VANOS Solenoid O-Ring Failure?

The B58 uses VANOS (variable valve timing) solenoids whose internal rubber O-rings degrade from heat and oil contamination, and the solenoid electronics can fail over time. A leaking O-ring lets oil pass where it should not and disrupts cam-timing control, producing rough running… Repairs typically run $200-$600. Severity: medium.

What is the 2019-2025 BMW M340i Valve Cover and Oil Filter Housing Gasket Oil Leaks (B58)?

The rubber valve-cover gasket and the oil filter housing gasket on the B58 inline-six harden and crack from repeated heat cycling, allowing engine oil to seep out. It typically appears from roughly 60,000-100,000 miles. Leaking oil can drip onto hot exhaust components (burning sm… Repairs typically run $400-$900. Severity: medium.

What is the 2019-2024 BMW M340i 12V Battery Drain and Failure / Battery Registration Issues?

M340i owners report the 12V AGM battery discharging or dying, sometimes on relatively young cars, often triggered by short-trip driving, parasitic drains from modules not entering sleep mode, or a failing Intelligent Battery Sensor (IBS). German owners on motor-talk specifically… Repairs typically run $300-$700. Severity: medium.

What is the 2020-2024 BMW M340i Turbo Wastegate Rattle at Idle?

The B58 engine's electronic wastegate actuator can develop play over time, producing a characteristic rattling or buzzing noise at idle and during deceleration. The wastegate flapper valve develops clearance within its housing, causing it to vibrate at certain RPMs. While often d… Repairs typically run $200-$2,000. Severity: low.

What is the 2019-2022 BMW M340i Seat Belt Warning Audio Failure (Recall, RAM Software)?

On certain 2019-2022 M340i vehicles, a software defect in the receiver audio module (RAM) control unit can prevent the car from generating the audible seat belt reminder chime for the driver. Without the audible warning, an unbelted driver may be less likely to buckle up, which f… Repairs typically run $0-$0. Severity: low.

All 11 Known Issues

When Issues Typically Appear

2020-2024 BMW M340i: Coolant Loss from Expansion Tank and Water Pump#

2020-2024 BMW M340i: High-Pressure Fuel Pump (HPFP) Failure#

2020 BMW M340i: Loss of Brake Assist from Brake Vacuum Pump Damage (Recall 21V-598)#

2020-2024 BMW M340i: Intake Valve Carbon Buildup#

2020-2024 BMW M340i: Oil Filter Disintegration in Housing#

2019-2025 BMW M340i: VANOS Solenoid O-Ring Failure#

2019-2025 BMW M340i: Valve Cover and Oil Filter Housing Gasket Oil Leaks (B58)#

2020-2024 BMW M340i: Turbo Wastegate Rattle at Idle#

2019-2025 BMW M340i: ZF 8HP Harsh / Jerky Low-Speed Shifting and Mechatronic Faults#

2019-2024 BMW M340i: 12V Battery Drain and Failure / Battery Registration Issues#

2019-2022 BMW M340i: Seat Belt Warning Audio Failure (Recall, RAM Software)#

Other BMW Models