AI Damage2020 BMW M340I: common problems
Owners of the 2020 BMW M340I filed 55 complaints with NHTSA, most often about engine and electrical system. The maker issued 251 service bulletins for this year. We found 5 repair videos on YouTube. Details by component below, with sources.
Key figures
- Owner complaints
- 55
- Technical service bulletins (TSB)
- 251
- YouTube repair videos
- 5
What fails most often
- 1 Engine 73% of all complaints
- 2 Electrical system 11% of all complaints
- 3 Engine and cooling 7% of all complaints
- 4 Fuel/propulsion system 5% of all complaints
- 5 Powertrain 4% of all complaints
- 6 Tires 4% of all complaints
- 7 Service brakes 2% of all complaints
- 8 Wheels 2% of all complaints
- Engine: 40 complaints (73% of all); manufacturer bulletins for this component: 9.
- Electrical system: 6 complaints (11% of all); manufacturer bulletins for this component: 115.
- Engine and cooling: 4 complaints (7% of all); manufacturer bulletins for this component: 19.
- Fuel/propulsion system: 3 complaints (5% of all).
- Powertrain: 2 complaints (4% of all); manufacturer bulletins for this component: 11.
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
- automatic, 8-speed
Drive: RWD, AWD
Symptoms owners describe
How many of the 55 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 | 40 | 0 | 9 |
| Electrical system | 6 | 0 | 115 |
| Engine and cooling | 4 | 0 | 19 |
| Fuel/propulsion system | 3 | 0 | 0 |
| Powertrain | 2 | 0 | 11 |
| Tires | 2 | 0 | 4 |
| Service brakes | 1 | 0 | 9 |
| Wheels | 1 | 0 | 6 |
| Equipment | 0 | 0 | 91 |
| Structure | 0 | 0 | 27 |
| Visibility | 0 | 0 | 17 |
| Backover prevention | 0 | 0 | 11 |
| Steering | 0 | 0 | 10 |
| Exterior lighting | 0 | 0 | 8 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
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…
Description: My 2020 BMW M340i xDrive has exhibited a persistent whining noise from the front drivetrain since approximately 38,000 miles. The noise varies with speed and load and appears to originate from the front differential.
The contact stated that after an oil change was performed by an independent mechanic, there was a large amount of gray smoke coming from the exhaust pipe while accelerating from a complete stop. There was no warning light illuminated during the failure.
The contact stated that upon starting the vehicle, the contact noticed a thick white smoke coming out of the exhaust pipes. In addition, the contact stated that there was an abnormal ticking sound coming from the engine while idling. There was no warning light illuminated.
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.
Electronic parking brake malfunction, disengage ineffective. Ongoing 2020 BMW mechanical issue, multiple dealer submissions, BMW refuses to open active recall. BMW requires $3,000 center panel replacement, out-of-pocket.
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
Comparison
By complaint count this model year ranks 829 of 2,102 model years in the NHTSA data (top 39% most complained about).
On average one model year of the M340I has 15 complaints (5 years in the data). This year has 55, above average.
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.
- Engine and cooling. Radiator and fan after a frontal hit, coolant level and condition, overheating.
- Fuel/propulsion system. Fuel smell, leaks, rough running, fuel-system codes.
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 Radiator Grilles Lower Active Air Flap Assembly limited warranty for defects in materials and/or workmanship has been extended to 15 years / 150,000 miles as determined from the original first in-service / delivery…
- The electrical system of BMW vehicles has been subject to an ongoing development process over the last few…
The electrical system of BMW vehicles has been subject to an ongoing development process over the last few years. This has led to increased demands being placed on the battery. This document covers important…
- Functional noises (squealing/honking) when braking shortly before the vehicle comes to a stop
- ?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
The following fault codes are stored during a vehicle test: 80419A - Left high-beam headlight: Short circuit and/or 8041A5 - light outputs: Number of permitted short circuit cycles exceeded
- Condensation is present on the inner surfaces in one or both taillights (circled)
- In the event of an accident, the two-battery Dual Storage System (DSS) is disconnected from the electrical…
In the event of an accident, the two-battery Dual Storage System (DSS) is disconnected from the electrical system via an internal relay.
- BMW AG has issued an Emissions Recall (effective March 17, 2023) on a certain Model Year 2021 - 2023 BMW…
BMW AG has issued an Emissions Recall (effective March 17, 2023) on a certain Model Year 2021 - 2023 BMW vehicles that were produced between June 16, 2020, and December 13, 2022. Due to a software failure, there is the…
- A vehicle arrives at your center to be diagnosed for a micro-leak in the fuel evaporative (EVAP) system…
A vehicle arrives at your center to be diagnosed for a micro-leak in the fuel evaporative (EVAP) system (NVLD natural vacuum leak detection). For this condition, the following fault is stored in the DME: 190302 - fuel…
- BMW AG has issued a Delivery Stop effective June 6, 2023 on certain Model Year 2023 - 2024 BMW vehicles…
BMW AG has issued a Delivery Stop effective June 6, 2023 on certain Model Year 2023 - 2024 BMW vehicles that were produced between October 26, 2022 and May 8, 2023.
- With the introduction of the BMW Remote Software Upgrade, all Service Pack 18 vehicles and partial Service…
With the introduction of the BMW Remote Software Upgrade, all Service Pack 18 vehicles and partial Service Pack 15 vehicles may receive new functionality or modifications in their features.
NHTSA lists 251 bulletins for this year; the 12 newest are shown here.
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.
Other years of this model
Questions and answers
What are the most common problems with the 2020 BMW M340I?
Owner complaints to NHTSA most often mention: engine, electrical system, engine and cooling. Total complaints: 55. The most frequent symptoms in complaint texts: engine failure or replacement (22%), warning lights, check engine (20%), smoke, burning smell, fire (11%).
How many service bulletins (TSB) were issued for the 2020 BMW M340I?
NHTSA lists 251 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.
Should I buy a 2020 BMW M340I from a US auction?
Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.
Other 2020 models
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.