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BMW M340IModel year report

2020 BMW M340I Problems

Complaints
57filed with NHTSA
Median mileage
37,331miles, 6 complaints with mileage
Recalls
10campaigns on record
Trend
RisingComplaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.
NHTSA crash rating
—no overall rating published
EPA fuel economy
25 mpgcombined, 3.0L 6-cyl RWD · 22 city / 30 hwy

Sources: NHTSA records for the 2020 BMW M340I (complaints, recalls, investigations), EPA fuel economy. Report an error

What owners report

Owners of this 2020 BMW M340i most often describe the B58 engine oil pump failing, with plastic internal parts that crack or break, leading to low oil pressure, sudden stalls, or engine damage. Complaints also often say the car can no longer read the oil level, and some describe starter faults or restarts that failed. Mileage is mostly not listed, but texts describe oil pump failures at about 15,000 to 55,000 miles.

  1. Engine

    Oil pump plastic parts fail, causing oil pressure loss

    • 34 complaints (60%)
    • median 59,015 mi at 6.0 yrs old (1 states mileage, few)
    • owner-quoted repair $6,000 (median of 7 quotes)
    • filed 2023–2026

    Owners describe an oil pump with plastic internal parts that crack, break, or collapse, leading to low oil pressure warnings, stalls, or engine failure while driving. Some say the failure came with little warning and that the car was towed to a dealer or shop. Complaints say a mechanic or the dealer found the oil pump had failed, and some reports say the replacement pump uses metal parts, while some owners say no recall has been issued for older pumps. Sample mileage is mostly not listed, but texts describe oil pump failures at about 15,000 to 55,000 miles.

    What to check: Ask whether the oil pump has been replaced with the updated metal-part design, and request the service records. A pre-purchase inspection can check for stored oil pressure fault codes and whether the oil level reads correctly on a warm engine.

    2 excerpts from owner complaints in NHTSA records

    “My oil pump went out causing Low pressure codes and resulting in me paying over 2 grand to get it repaired, They super seeded the oil pump they used to use with a new one and theirs many other reports online etc of the 2020 bmw m340 oil pump going out due to plastic internals which can lead to engine failure .”

    NHTSA complaint #11697131, filed 2025-11

    “Plastic components in the oil pump went out. BMW has made new oil pumps with metal components that are less fragile and do not fail as often. Outside of warranty these repairs can be very costly. I have had to pay out of pocket for these repairs myself. I do not understand why this is not a recall.”

    NHTSA complaint #11772856, filed 2026-10
  2. Engine

    Oil level cannot be read by the car

    • 24 complaints (42%)
    • typically at 5.3 yrs old
    • owner-quoted repair $6,000 (median of 7 quotes)
    • filed 2023–2026

    Owners describe the electronic oil level measurement failing, with some saying the reading stops working at a certain level and others saying it fails once the engine is fully warm. Owners say the fault is often treated as a sign of oil pump failure, and that the dealer or a shop tied it to the oil pump. Some owners say the oil pump replacement was paid out of pocket after the warranty had ended. Mileage is mostly not listed, though a text describes the oil level problem at about 42,000 miles.

    What to check: Ask whether the oil level reads correctly on a warm engine, and check for stored oil pressure or oil level fault codes with a scan tool. Ask the seller to confirm whether the oil pump has been replaced with the updated design.

    2 excerpts from owner complaints in NHTSA records

    “I am unable to read the oil level in my 2020 M340i. Upon checking the oil pressure, the oil pressure goes above 45psi which is the cutoff for the measurement check. Under heavy acceleration, the oil pressure will go over 90psi. My car needs the oil pump to be replaced. The plastic ring surrounding the oil pump for variable oil pressure will crack and lead to a high oil pressure scenario, eventually leading to catastrophic engine damage. …”

    NHTSA complaint #11648849, filed 2025-03

    “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.”

    NHTSA complaint #11658972, filed 2025-05
  3. Electrical system

    Starter faults and failed restarts

    • 15 complaints (26%)
    • median 55,331 mi at 5.8 yrs old (2 state mileage, few)
    • owner-quoted repair $6,000 (median of 5 quotes)
    • filed 2024–2026

    Owners describe a starter that fails, sometimes after repeated start attempts, with electrical damage, overheating warnings, burning smells, or smoke reported. Some say the car stalled, could not be restarted, and had to be towed, and in one of these cases a repair under a recall did not stop the problem from returning. Complaints also describe delayed or unclean starts and an engine that would not restart after a start-stop shutdown. Where mileage is given, the starter reports describe problems at about 28,000 to 38,000 miles.

    Recall 24V5760002 related service bulletins

    What to check: Ask whether the starter and 12-volt battery have been tested, and whether any sleep-mode software bulletin was applied if the car has a no-start history.

    2 excerpts from owner complaints in NHTSA records

    “Brought my car in for a starter recall picked it up next day and drove home then came out to turn my vehicle on again and it wouldn’t start. Burning smell from engine bay as well. Returned the car they inspected it and told me a faulty starter. When I brought the car in it was in perfect working condition I only brought it for the recall. I was then held accountable for 25% of repair costs.”

    NHTSA complaint #11610022, filed 2024-08

    “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.”

    NHTSA complaint #11655346, filed 2025-04

Buying note. Someone considering this model year may want a pre-purchase inspection that checks whether the oil level reads correctly on a warm engine and whether the oil pump has been replaced with the updated design. Asking for service records and any stored oil pressure or starter fault codes can help a buyer weigh these reports.

Summary written with AI from a sample of 48 NHTSA complaints for this model year (picked at random, with complaints that state a mileage and recent ones taken first), then checked automatically against the source records. Where a problem shows a complaint count, every complaint for this model year was matched with fixed keyword rules (written with AI and tested against the sample), and the mileage, age and repair figures are calculated from those complaints; owners' figures are as stated, not verified. Other counts refer to the sample. The excerpts come from NHTSA's public complaint records and are unverified; capitalisation is normalised, NHTSA staff notes are removed, and shortened text ends with “…”. Something wrong? Request a correction.

NHTSA recorded 57 consumer complaints for the 2020 BMW M340I. 6 of the complaints include a mileage, and 67% of those were filed for vehicles with under 50,000 miles; the median is 37,331 miles. NHTSA lists 10 recall campaigns and 251 technical service bulletins for this model year.

Not compared (fewer than 3 comparable model years). Model years 2008–2023 of the same vehicle that have at least 25 complaints are compared, and a model needs at least 3 of them.

Which parts are reported most

Complaints can name more than one part, so the counts add up to more than the total. Select a part to see its complaints, recalls and bulletins.

Example complaints

Engine: “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.”

NHTSA complaint #11631042, filed 2024-12

Other or unknown: “I was driving on the highway at approximately 70 MPH, the posted limit, when all of a sudden the sunroof exploded. It sounded like a gunshot and I almost lost control of the vehicle. Luckily the headliner was closed so the glass did not enter the cabin. There were no vehicles in front of us for at least 1 mile and no overpasses or rocks that I saw or heard hitting the vehicle. It is a stock vehicle with 5200 miles on it.”

NHTSA complaint #11339650, filed 2020-07, 5,100 miles

Electrical system: “Engine starter was faulty resulting in repeated attempts to start the engine using excessively long starting attempts and warnings from my car of overheating. At a traffic light, my car went into auto-off and then shut down and I was unable to restart the car leaving me stuck at a busy intersection. I received police support and a tow to the BMW Buena Park dealership. The dealership informed me the issue could be related to an open recall (B120524) which relates to the starter. The dealership replaced the starter but claims the issue is not related to the recall. …”

NHTSA complaint #11629307, filed 2024-12

Engine cooling: “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 vehicle had not yet been diagnosed or repaired. The manufacturer had yet to be notified of the failure. The failure mileage was approximately 82,500.”

NHTSA complaint #11707622, filed 2025-12, 82,500 miles

Mileage when problems were reported

67% of the 6 complaints with a mileage were filed for vehicles with under 50,000 miles; the middle half falls between 15,000 and 59,015 miles.

17%0–1017%10–2533%25–5017%50–7517%75–1000%100–1500%150+
Share of complaints by mileage when the problem was reported, in thousands of miles (6 complaints with mileage). Red bars: under 50,000 miles. Bucket widths differ. Median: 37,331 miles.

Complaints by year filed

Trend: rising. Complaints filed in the last 3 full calendar years are at least 25% higher than in the 3 years before.

20202021202320242025202624
Complaints by year the complaint was filed with NHTSA. Red bars: the last 3 full calendar years used for the trend. The current year (2026) is partial.

Fuel economy and running cost

EPA ratings for each 2020 BMW M340I version. Annual fuel cost is the EPA's estimate at its current fuel prices for 15,000 miles a year (55% city driving).

VersionEngineTransmissionCityHwyComb.Fuel / yr
M340i RWD3.0L 6-cyl8-speed automatic223025$3,300
M340i xDrive AWD3.0L 6-cyl8-speed automatic223025$3,300

Source: U.S. EPA and Department of Energy, fueleconomy.gov. Ratings are for comparing vehicles; real-world mileage varies with driving and conditions.

Recalls and investigations

See all 10 recalls for the 2020 BMW M340I → · Check a VIN at nhtsa.gov/recalls

Technical service bulletins

TSBs are manufacturer notes to dealers about known repair procedures. They are not recalls and do not by themselves mean a vehicle has a fault. 251 on record; the latest 10 are shown.

See all 251 bulletins →

Other model years of the BMW M340I

YearComplaintsMedian miRecallsCrash ★MPGScore (50 = typical)Trend
202273001—26—Not enough data
2021114,0006—26—Not enough data
20205737,33110—25Not compared (fewer than 3 comparable model years)Rising

All BMW M340I model years

Frequently asked questions

What are the most common problems with the 2020 BMW M340I?

Owners of this 2020 BMW M340i most often describe the B58 engine oil pump failing, with plastic internal parts that crack or break, leading to low oil pressure, sudden stalls, or engine damage. The issues reported most often: Oil pump plastic parts fail, causing oil pressure loss; Oil level cannot be read by the car; Starter faults and failed restarts.

How many NHTSA complaints does the 2020 BMW M340I have?

NHTSA recorded 57 consumer complaints for the 2020 BMW M340I as of Oct 28, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.

What part of the 2020 BMW M340I is reported most often?

Engine is named most often, in 42 complaints (74% of the total), followed by other or unknown with 9.

Has the 2020 BMW M340I been recalled?

NHTSA lists 10 recall campaigns for this model year. To check a specific vehicle, enter its VIN at nhtsa.gov/recalls.

What gas mileage does the 2020 BMW M340I get?

The EPA rates the 2020 BMW M340I (M340i, 3.0L 6-cyl) at 25 mpg combined, 22 city and 30 highway, with an estimated annual fuel cost of $3,300 at 15,000 miles a year. Other engine and drive versions are rated differently.

At what mileage are problems with the 2020 BMW M340I reported?

Among the 6 complaints that include a mileage, the median is 37,331 miles and the middle half falls between 15,000 and 59,015 miles; 67% were filed for vehicles with under 50,000 miles.

About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 28, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate. Fuel economy is from the EPA and DOE (fueleconomy.gov).

Complaint counts come from NHTSA’s public complaint database; we count each complaint once. The source records for this vehicle are on nhtsa.gov. Scores and trends are our own summaries of that data, described in the methodology. This page is not legal, safety or repair advice: for a specific vehicle, check its VIN at nhtsa.gov/recalls and ask a qualified mechanic. See an error? Tell us.