M340I

BMW M340i Problems

What actually breaks on the BMW M340i — 64 owner complaints filed with NHTSA across 2020–2022, sorted by model year and by system, with what owners wrote in their own words.

NHTSA owner complaints · 64 reports · 42 builds · Updated Aug 5, 2026
Quick answer

Owners have filed 64 complaints on the BMW M340i, covering 2020–2022. The system named most often is Engine (30 reports). Worst years by volume: 2020, 2021, 2022; cleanest: 2022, 2021, 2020. On average the car was 3.9 years old when the problem happened.

What breaks on BMW M340i

Grouped by the system owners named — percentages are shares of all 64 M340i complaints. Open any row for the full reports in owners' own words.

Engine 47% 30 Read
2022 BMW M340i

Water pump failure and coolant reservoir leak

2021 BMW M340i

At approximately 20,000 miles, vehicle indicated excessively low oil. The dealer indicated oil level was excessively low but did not identify the problem,. The vehicle was filled and returned to owner. Within 1000 miles, the incident occurred again. Dealer replaced replaced the valve cover claiming that was the issue.…

2021 BMW M340i

At approximately 20,000 miles, vehicle indicated excessively low oil. The dealer indicated oil level was excessively low but did not identify the problem,. The vehicle was filled and returned to owner. Within 1000 miles, the incident occurred again. Dealer replaced replaced the valve cover claiming that was the issue.…

Electrical System 11% 7 Read
2022 BMW M340i

The starter in my 2022 BMW M340I sedan was faulty after 54,000 miles. It began to take two attempts to start the vehicle each time and was at risk of not starting. The first attempt all electrical components would turn on but the ignition was unable to start the engine. Then the second attempt was generally…

2021 BMW M340i

I have been smelling a burning odor in the vehicle for almost a year which the dealership and an independent shop had not been able to diagnose. The car was recently throwing Drivetrain Error codes which prompted a visit to the dealership. They found that the 48v battery and negative cable are burnt and quoted $5680…

2020 BMW M340i

The ignition start is not clean and delayed. There is already a recall 25V-644. There is "No remedy available" for this model per inquiry with local BMW dealer in Buffalo NY 14221 made 3 weeks ago. I am fearful of an electrical fire from overheating. I do smell an intermittent burning smell but it may in the outside…

Power Train 8% 5 Read
2021 BMW M340i

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…

2021 BMW M340i

While driving through an intersection and making a left turn, a failure of the engine water pump pulley caused the pulley to break apart. This led to damage to the coolant line and tensioner, sudden coolant loss, and the serpentine belt slipping off. The failure occurred mid-turn, causing the vehicle to skid and…

2021 BMW M340i

Here’s a strong version that sounds frustrated but still credible and harder to dismiss: I’ve owned many vehicles over the years, and this BMW has been, without question, the most problematic car I’ve ever had. The list of issues has been absurd for a vehicle in this price range and from a brand that markets itself as…

Engine And Engine Cooling 6% 4 Read
2020 BMW M340i

The contact owns a 2020 BMW M340I. 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 vehicle was taken to…

2020 BMW M340i

The contact owns a 2020 BMW M340I. 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…

2020 BMW M340i

The contact owns a 2020 BMW M340I. The contact stated that the vehicle was repaired under NHTSA Campaign Number: 24V576000 (Electrical System, Engine and Engine Cooling); however, the repair failed to prevent the failure from occurring. The contact stated that shortly after the recall repair was completed, the vehicle…

Steering 3% 2 Read
2022 BMW M340i

The contact owns a 2022 BMW M340I. The contact stated that after starting the vehicle, the power steering failure message was displayed, and the steering wheel was difficult to turn in either direction. After approximately one hour, the vehicle was restarted, the failure was self-corrected, and the steering wheel…

2021 BMW M340i

Started as low creaking noise coming from front left wheel. Slow speeds, over small bumps. Over time (one month), creaking noises became louder and more frequent. At that time, steering was starting to feel stiff when turning to the left. Taken to 2 BMW dealerships who said it was just a noise and that both tie rods…

Service Brakes 3% 2 Read
2022 BMW M340i

The brakes failed at high speed. Yes the vehicle is available for inspection. The car hit a barrier and flipped on its roof. Yes, I and my passenger were both at risk of serious injury. No independent confirmation has taken place at this time. No warning lights indicated malfunction

2020 BMW M340i

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

Tires 3% 2 Read
2020 BMW M340i

I have owned my 2020 BMW m340iX for 2 years. During that time I have had 5 tires blow out, including 3 in the past 3 months alone. The tires are "run flat" and need to be completely replaced if they develop any issues. The dealer I use for service, who is owned by the manufacturer, says it is simply wear and tear -…

2020 BMW M340i

The contact owns a 2020 bmw m340i, equipped with pirelli tires, tire line: p7 cinturato, tire size 225/40/r19, DOT number: not available. The contact stated that while the vehicle was at an independent mechanic for suspension inspection, the mechanic became aware of bubbles in the driver's and passenger's side front…

Fuel/propulsion System 3% 2 Read
2020 BMW M340i

Oil pump appears to have failed. Told plastic components inside pump. BMW issued a new part number and changed pump to all metal internals. This is standard on later production dates now. Pump failure causes engine failure and oil gauge failure to read out. Head gasket replacement which may or may not be related

2020 BMW M340i

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…

M340i years to avoid — and the clean ones

Complaints per model year. More reports usually means more cars on the road as well as more trouble, so read the crash and fire columns alongside the count.

FIG.02·BMW M340i complaints by model year
Model yearComplaintsTop systemCrashesFires
20226Air Bags
202111Electrical System,engine
202047Electrical System
ROWS 3·SOURCE NHTSA owner complaints

The same model year, different builds

Every complaint carries the first 11 characters of the VIN — plant, year, body and engine. That is a production series, and complaints are spread across them very unevenly.

FIG.03·BMW M340i complaints by production series
MeasureValue
Distinct production series42
Average complaints per series1.5
Worst single series4 complaints
Average age at failure3.9 years
ROWS 4·SOURCE NHTSA owner complaints + ForCar

A model average of 1.5 hides a worst series at 4. Enter a VIN above to see the numbers for that exact build instead of the model as a whole.

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How we count

Every figure here comes from complaints owners filed with NHTSA — 1,100,006 of them, covering 1,982 models built between 1981 and 2026.

A complaint is an unverified report: someone wrote down what happened to their car. It is not a confirmed defect and not a recall. What makes the volume useful is the pattern — when thousands of owners of the same build describe the same failure, that is a signal no marketing brochure will give you.

Two things we do that the source does not. First, we compute the age of the car at the moment of failure from the incident date and the model year. Second, we group complaints by the first 11 characters of the VIN — the production series — so a bad plant run does not disappear into a model-wide average.

Frequently asked questions

What are the worst years for the M340i?

By complaint volume, 2020, 2021, 2022 drew the most owner reports. Bear in mind that popular years put more cars on the road, so check the crash and fire columns too.

Which M340i years are the cleanest?

2022, 2021, 2020 have the fewest complaints on file. For recent years that can simply mean the cars are young.

How many complaints does the BMW M340i have?

64 owner complaints filed with NHTSA, covering 2020–2022. Of those, 0 describe a crash and 0 a fire.

Are these complaints verified?

No. They are unverified reports from owners. NHTSA publishes them as filed and investigates only a fraction. The value is in the pattern, not in any single report.

Can I check complaints for one specific car?

Yes — enter its VIN above. We match the first 11 characters, which identify the plant, year, body and engine, so you get complaints on that exact production series rather than the whole model.

Owner complaints from NHTSA, published as filed and unverified. Age at failure computed by ForCar from incident date and model year; production series grouped by the first 11 VIN characters. Last updated Aug 2026. — ForCar Reviewed by , founder of ForCar.