Problems · NHTSA complaints

2021 BMW 3 Series problems

Owners filed 44 complaints about the 2021 BMW 3 Series with NHTSA between Dec 2021 and Sep 2026. The most-cited component is engine (18).

Complaints
44
Filed with NHTSA
Crashes
1
Reported by owners
Fires
3
Reported by owners
Injuries
2
People reported injured
Deaths
0
Reported to NHTSA
01 —By component

Complaints by component

One complaint can cite several components
  1. Engine18
  2. Electrical system17
  3. Power train6
  4. Air bags4
  5. Suspension3
  6. Service brakes3
  7. Forward collision avoidance3
  8. Fuel/propulsion system2
  9. Steering2
  10. Lane departure2
  11. Engine and engine cooling1
  12. Wheels1
  13. Visibility/wiper1
  14. Structure1

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.

Data from NHTSA Complaints API · synced Nov 4, 2026NHTSA vehicle page
02 —Trend

When complaints were filed

Does it get worse with age? Complaints per calendar year filed
View as table
Model yearComplaints filed per calendar year
20211
20224
20234
20242
202514
202619

Mileage at failure isn’t a structured field in NHTSA complaint data, so we don’t chart it. Some owners mention it in their reports below.

03 —Owner reports

Top problems in owners’ words

Verbatim from NHTSA complaints, newest first

Engine

18 reports1 fire
“I am getting error code 21A50A and 216115 which Starter Overheating that can cause fire. Similar error code were coming on other cars and BMW have recalled it the recall number is 26V056. I ask BMW and NHTSA to include 330E in this recall as 330E is similar to 330I. 330I and 330E uses same parts and similar design and excluding the 330E from this recall doesn't make sense.”
Owner complaint to NHTSAFiled Sep 2, 2026EngineODI 11761564

Electrical system

17 reports3 fires3 related recalls
“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 to replace the battery and cables. After investigating I found that there were recalls for this issue on other BMWs, including the same year and model of my vehicle, but my VIN is not pulling up a recall. The issue is a fire risk and a very expensive repair that should be covered by the manufacturer due to a known defect.”
Owner complaint to NHTSAFiled Jul 2, 2026Electrical system, EngineODI 11747887

Power train

6 reports
“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 a premium luxury manufacturer. The sunroof failed, I’ve had multiple tire blowouts under normal driving conditions, the drive bar/suspension was bent from what should have been a routine road bump, the engine oil housing/component failed, and now I’m dealing with coolant system and drivetrain problems as well. At this point, it feels like one major issue after another. I expected quality, reliability, and engineering excellence from BMW, but my experience has been the complete opposite. Instead, ownership has been stressful, expensive, and incredibly disappointing. A luxury vehicle should not have this many significant failures in such a short span of ownership. Between the repair costs, downtime, and constant concern over what will fail next, this car has completely destroyed my confidence in the BMW brand. I am documenting these issues formally…”
Owner complaint to NHTSAFiled May 18, 2026Power train, Electrical system, Fuel/propulsion systemODI 11738468

Air bags

4 reports1 crash
“The contact owns a 2021 BMW 330I. The contact stated that while entering the vehicle, there was an audible alert heard, and a red air bag light was displayed on the instrument panel. The vehicle was taken to the dealer, where it was diagnosed with a failure in the driver’s side knee air bags. The air bags were replaced, and the airbag module was reprogrammed. The manufacturer was notified of the failure. The failure mileage was 30,868.”
Owner complaint to NHTSAFiled Jul 17, 2026Air bagsODI 11751173

Suspension

3 reports
“I bought my car in 2023 with 12,000 miles. I currently have 43,000 on it. I don’t drive it hard and have always had the maintenance done. I had my rear brakes replaced today at BMW and I was told my engine mounts have failed and need to be fixed asap. Was given a quote of 3000.00. My warranty expired literally 2 months ago. I’m told it’s dangerous to drive but how does this happen? Everything I read says they should be lasting 60,000-100,000 miles at least.”
Owner complaint to NHTSAFiled Nov 21, 2025SuspensionODI 11700913

Service brakes

3 reports1 crash
“Going into a parking spot. Applied brakes, then the car did not brake, then it accelerated hitting a Jeep and finally stopped when the driver side front hit a parking barrier and then the air bags deployed. Sudden unintended acceleration was the cause of this accident. Car was totaled.”
Owner complaint to NHTSAFiled Jan 1, 2025Air bags, Service brakes, Forward collision avoidanceCrash reportedODI 11633498
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 4, 2026

Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.