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NHTSA FEDERAL EVIDENCE AUDITAudited: 2026-08-25

2021 Acura TLX Common Problems & Defect Telemetry

Authoritative defect intelligence synthesized from 65 verified NHTSA owner complaints, 4 federal safety recalls, and interquartile failure mileage telemetry.

Data Grade: MEDIUM16 Odometer Verified EntriesMethodology
Executive AI Defect Summary

The 2021 Acura TLX receives a 4.1/10 MazicBay Reliability Index based on 65 verified NHTSA federal complaints and 4 safety recalls. The primary reported failure mode is Transmission Hesitation, Hard Shifting & Slipping Reports with a median failure point at 55,300 miles (IQR: 23,16677,500 mi). Out-of-warranty repairs benchmark at $1,400 – $3,800 .

2021 Acura TLXLuxury2021
DLC Port: Driver footwell below steering column

*Representative vehicle platform imagery. Body styling varies across generations.

MazicBay Reliability Index
4.1 / 10

32.5 complaints / 10k sold

NHTSA Owner Complaints
65

Verified US federal records

Safety Severity Grade
Critical Risk

Crash, fire & stall audit

Federal Safety Recalls
4

4 Active / Free Remedies

Switch TLX Model Year (2014–2025)
NHTSA Defect Subsystem Breakdown

2021 TLX Failure Distribution by Vehicle Subsystem

100% Normalized Telemetry
38%26%16%12%
Engine & Powertrain:38%
Electrical & Sensors:26%
Steering & Suspension:16%
Brakes & ABS Hydraulics:12%
Airbags & Body Structure:8%
Defect Clustering

Top Reported Problem Clusters (7)

Ranked by NHTSA Complaint Frequency
#1 TRANSMISSION & DRIVETRAINMedium Severity87% Match Confidence

Transmission Hesitation, Hard Shifting & Slipping Reports

26
Federal Complaints
Failure Mileage (Median):55,300 milesIQR: 23,16677,500 mi
Estimated Repair Cost:$1,400 – $3,800 MazicBay Repair Intelligence Model
Recall Status:Out-of-Pocket / TSB RemedyNHTSA Campaign Audit
Reported Defect Symptoms
  • Hard gear shifts / delayed engagement into Drive/Reverse
  • Transmission shudder / jerking under acceleration
  • Transmission slipping between gears
Potentially Associated OBD-II Codes

Correlated via MazicBay Diagnostic Engine (not NHTSA verified fact).

Sample Verified NHTSA Evidence Records (3)
ODI #11754848 • Filed: 08/04/2026

I'm losing power than normal all of a sudden. When I step on the gas after light hits green in sport and sport plus mode my car losses traction even when traction control is on, and I hear a loud clunck sound. After the the loud clunck sound the car losses RPM while driving I ...

ODI #11750163 • Filed: 07/13/2026

I took this vehicle to get serviced in the summer of 2025. I recently joined an Acura Type S (2021+) group on Facebook and learned that the issue is quite prevalent. I had to have the transmission and transfer case replaced due to transmission issues and traction issues

ODI #11748958 • Filed: 07/08/2026

On July 7th 2026 I was driving home, came to a stop light at normal speed, when the light turned green I took off at normal speed and I heard a huge cluck / bang from underneath the car and it bogged and didn’t want to move. I then stepped on the gas because of the Car behind ...

#2 BRAKING SYSTEM & ABSCritical Severity77% Match Confidence

Service Brakes, ABS Actuator & Master Cylinder Reports

17
Federal Complaints
Failure Mileage (Median):9,608 milesIQR: 5,80413,411 mi
Estimated Repair Cost:$350 – $1,100 MazicBay Repair Intelligence Model
Recall Status:Under Investigation / Recall AuditNHTSA Campaign Audit
Reported Defect Symptoms
  • Spongy or hard brake pedal travel
  • ABS / Brake warning light illuminated
  • Extended stopping distance / pedal vibration
Potentially Associated OBD-II Codes

Correlated via MazicBay Diagnostic Engine (not NHTSA verified fact).

Sample Verified NHTSA Evidence Records (3)
ODI #11747673 • Filed: 07/01/2026

On 07/01/2026, at approximately 8:00 AM, during steady acceleration, flashing of MIL with loss of power presented northbound after merging from 235 west bound to I-135 north bound near Park City, KS. Particularly dangerous resulting in near rear end collision. Upon taking near...

ODI #11723440 • Filed: 03/10/2026

Driving towards the gas station, still at lows speeds while I was in the neighborhood so speed limit was 15mph. I can hear and feel the car struggle to move forward, about 2 minutes into the drive a hear a big TOON and check engine light is on for about a minute before going a...

ODI #11717853 • Filed: 02/13/2026

Adaptive Damper System error on dashboard. Took the car to the dealer and they confirmed two issues. Codes C1646-14 and C1647-14 indicating the stroke sensor has lower limit abnormality. Dealer recommended replacing both rear shocks due to over extension. Once shocks were repl...

#3 ELECTRICAL SYSTEM & BATTERYCritical Severity76% Match Confidence

Electrical Parasitic Drain, Infotainment & Harness Reports

15
Federal Complaints
Failure Mileage (Median):2,638 milesIQR: 2,3192,956 mi
Estimated Repair Cost:$280 – $850 MazicBay Repair Intelligence Model
Recall Status:Out-of-Pocket / TSB RemedyNHTSA Campaign Audit
Reported Defect Symptoms
  • Unexplained battery drain after sitting overnight
  • Infotainment display / instrument cluster blackouts
  • Accessory malfunction / alternator fault warnings
Potentially Associated OBD-II Codes

Correlated via MazicBay Diagnostic Engine (not NHTSA verified fact).

Sample Verified NHTSA Evidence Records (3)
ODI #11739426 • Filed: 05/22/2026

Transfer case failure. I was driving my 2021 Acura TLX Type S when I suddenly heard a loud pop from underneath the car. Right after that, the SH AWD system stopped working and the car was only driving in front wheel drive. There were no warning lights or signs before it happen...

ODI #11738440 • Filed: 05/17/2026

Dealers are investigating and need replacing rear shocks/solenoids, stroke sensors, and wiring harnesses. The issue is commonly identified as corrosion in the rear stroke sensor wiring harness or faulty damper make "Adaptive Damper System" (ADS) error light on and can't not ma...

ODI #11717853 • Filed: 02/13/2026

Adaptive Damper System error on dashboard. Took the car to the dealer and they confirmed two issues. Codes C1646-14 and C1647-14 indicating the stroke sensor has lower limit abnormality. Dealer recommended replacing both rear shocks due to over extension. Once shocks were repl...

#4 STEERING & SUSPENSIONMedium Severity65% Match Confidence

Electric Power Steering Assist & Suspension Noise Reports

15
Federal Complaints
Failure Mileage (Median):2,000 milesIQR: 2,0002,000 mi
Estimated Repair Cost:$450 – $1,400 MazicBay Repair Intelligence Model
Recall Status:Out-of-Pocket / TSB RemedyNHTSA Campaign Audit
Reported Defect Symptoms
  • Sudden loss of electric power steering assist
  • Steering wheel pull or highway wander
  • Clunking / knocking noise over bumps
Potentially Associated OBD-II Codes

Correlated via MazicBay Diagnostic Engine (not NHTSA verified fact).

Sample Verified NHTSA Evidence Records (3)
ODI #11739131 • Filed: 05/20/2026

I drive a 2021 Acura TLX 2.0 L turbo 4 cylinder. I was driving to work on ... on a busy street in Boyle Heights, Ca. When all of sudden I get a warning indicator “engine temp is high do not drive”. Pulled over immediately. Good thing I was in the far right lane and was able to...

ODI #11738440 • Filed: 05/17/2026

Dealers are investigating and need replacing rear shocks/solenoids, stroke sensors, and wiring harnesses. The issue is commonly identified as corrosion in the rear stroke sensor wiring harness or faulty damper make "Adaptive Damper System" (ADS) error light on and can't not ma...

ODI #11723440 • Filed: 03/10/2026

Driving towards the gas station, still at lows speeds while I was in the neighborhood so speed limit was 15mph. I can hear and feel the car struggle to move forward, about 2 minutes into the drive a hear a big TOON and check engine light is on for about a minute before going a...

#5 ENGINE & COOLINGMedium Severity67% Match Confidence

Engine Stalling, Oil Consumption & Cooling Defect Reports

13
Federal Complaints
Failure Mileage (Median):29,800 milesIQR: 15,90057,050 mi
Estimated Repair Cost:$950 – $3,200 MazicBay Repair Intelligence Model
Recall Status:Out-of-Pocket / TSB RemedyNHTSA Campaign Audit
Reported Defect Symptoms
  • Engine sudden stall / hesitation while driving
  • Abnormal oil burning / consumption
  • Check Engine Light (MIL) flashing
  • Engine overheating / coolant loss
Potentially Associated OBD-II Codes

Correlated via MazicBay Diagnostic Engine (not NHTSA verified fact).

Sample Verified NHTSA Evidence Records (3)
ODI #11747673 • Filed: 07/01/2026

On 07/01/2026, at approximately 8:00 AM, during steady acceleration, flashing of MIL with loss of power presented northbound after merging from 235 west bound to I-135 north bound near Park City, KS. Particularly dangerous resulting in near rear end collision. Upon taking near...

ODI #11743423 • Filed: 06/11/2026Odometer: 29,800 mi

2021 Acura TLX Type S SH-AWD. Total mechanical failure of PTU/transfer case spline interface at 29,800 miles within factory powertrain warranty. Vehicle operated silently in FWD-only with no warning lights, no fault codes, and no dashboard alerts — consistent with all complain...

ODI #11739131 • Filed: 05/20/2026

I drive a 2021 Acura TLX 2.0 L turbo 4 cylinder. I was driving to work on ... on a busy street in Boyle Heights, Ca. When all of sudden I get a warning indicator “engine temp is high do not drive”. Pulled over immediately. Good thing I was in the far right lane and was able to...

#6 AIRBAGS & SAFETY RESTRAINTSCritical Severity87% Match Confidence

Airbag Occupant Detection & Inflator Defect Reports

7
Federal Complaints
Failure Mileage (Median):17,215 milesIQR: 17,21517,215 mi
Estimated Repair Cost:$400 – $1,200 MazicBay Repair Intelligence Model
Recall Status:Under Investigation / Recall AuditNHTSA Campaign Audit
Reported Defect Symptoms
  • SRS Airbag warning lamp illuminated
  • Passenger occupant classification sensor failure
  • Seat belt retractor lockup
Potentially Associated OBD-II Codes

Correlated via MazicBay Diagnostic Engine (not NHTSA verified fact).

Sample Verified NHTSA Evidence Records (3)
ODI #11710022 • Filed: 01/09/2026Odometer: 17,215 mi

To Whom It May Concern: The purpose of my complaint is to bring to your attention reprehensible policies and misconduct displayed by the automaker, Acura, the premium subsidiary brand of the American Honda Motor Company. On 11/18/2025, I brought in my 2021 Acura TLX Tech w/SH-...

ODI #11665968 • Filed: 06/10/2025

The contact owned a 2021 Acura TLX. The contact received a notification of NHTSA Campaign Number: 24V064000 (Air Bags) however, the part to do the recall repair was not yet available. The contact stated that while accelerating from a stop, she was struck by another vehicle dri...

ODI #11629335 • Filed: 12/06/2024

The contact owns a 2021 Acura TLX. The contact received notification of NHTSA Campaign Number: 24V064000 (AIR BAGS); however, the part to do the recall repair was unavailable. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repa...

#7 FUEL SYSTEM & INJECTIONLow Severity65% Match Confidence

Fuel Pump Pressure Loss & Fuel Delivery Defect Reports

1
Federal Complaints
Failure Mileage (Median):55,000 milesIQR: 35,00075,000 mi
Estimated Repair Cost:$650 – $1,250 MazicBay Repair Intelligence Model
Recall Status:Out-of-Pocket / TSB RemedyNHTSA Campaign Audit
Reported Defect Symptoms
  • Sudden loss of propulsion power at highway speeds
  • Extended engine cranking / failure to restart
  • Fuel odor near fuel tank / engine bay
Potentially Associated OBD-II Codes

Correlated via MazicBay Diagnostic Engine (not NHTSA verified fact).

Sample Verified NHTSA Evidence Records (1)
ODI #11716343 • Filed: 02/06/2026

My gas tank is failing from the fuel seal, my safety is in danger since it throws a lot of gasoline, take the car to the dealer but they say it's not a factory problem

Safety Enforcement

Official NHTSA Safety Recalls (4)

100% Free Dealer Repair
NHTSA Campaign #24V064000Reported: 01/02/2024

AIR BAGS:SENSOR:OCCUPANT CLASSIFICATION:FRONT PASSENGER

Summary: Honda (American Honda Motor Co.) is recalling certain 2020-2022 Pilot, Accord, Civic sedan, HR-V, Odyssey, 2020 Civic coupe, Fit, 2021-2022 Civic hatchback, 2021 Civic Type R, Insight, 2020-2021 CR-V, CR-V Hybrid, Passport, Ridgeline, Accord Hybrid, 2020 Acura MDX, 2022 Acura MDX, 2020-2022 Acura RDX, and 2020-2021 Acura TLX vehicles. The front passenger seat weight sensor may crack and short circuit, failing to suppress the air bag as intended.

Safety Consequence: An air bag that deploys unintentionally during a crash can increase the risk of injury.
Manufacturer Remedy: Dealers will replace the seat weight sensors, free of charge. Owner notification letters were mailed March 28, 2024. This is a phased recall. Owners may contact Honda customer service at 1-888-234-2138. Honda's numbers for these recalls are XHP and VHQ.
NHTSA Campaign #24V950000Reported: 19/12/2024

FUEL SYSTEM, GASOLINE:STORAGE:TANK ASSEMBLY

Summary: Acura (American Honda Motor Co.) is recalling certain 2021-2023 TLX vehicles. The fuel filler neck and fuel tank may have been improperly welded, which can result in a fuel leak.

Safety Consequence: A fuel leak in the presence of an ignition source increases the risk of a fire.
Manufacturer Remedy: Dealers will replace the fuel tank assembly, free of charge. Owner notification letters were mailed February 3, 2025. Owners may contact Honda customer service at 1-888-234-2138. Acura's number for this recall is JKX.
NHTSA Campaign #25V391000Reported: 12/06/2025

SERVICE BRAKES, HYDRAULIC:PEDALS AND LINKAGES

Summary: Honda (American Honda Motor Co.) is recalling certain 2021-2025 Acura TLX, 2023-2025 Acura MDX, and 2023-2025 Honda Pilot vehicles. The brake pedal pivot pin was not secured properly, which can cause the pedal to shift out of position. As such, these vehicles fail to comply with Federal Motor Vehicle Safety Standard numbers 108, "Lamps, Reflective Devices, and Associated Equipment" and 135, "Light Vehicle Brake Systems."

Safety Consequence: A brake pedal that shifts out of position can prevent the driver from applying the brakes as intended, increasing the risk of a crash or injury.
Manufacturer Remedy: Dealers will inspect and replace the brake pedal assembly as necessary, free of charge. Owner notification letters were mailed July 29, 2025. Owners may contact Honda's customer service at 1-888-234-2138. Honda's numbers for this recall are FLX and XLY.
NHTSA Campaign #26V332000Reported: 21/05/2026

AIR BAGS:SENSOR:OCCUPANT CLASSIFICATION:FRONT PASSENGER

Summary: Honda (American Honda Motor Co.) is recalling certain 2018-2021, 2023 Acura TLX, 2019-2024 RDX, 2017-2020, 2022-2026 MDX, 2017-2021, 2023, 2025 Honda Ridgeline, 2017-2022 Pilot, 2019-2021 Passport, 2018-2026 Odyssey, 2019-2022 Insight, 2019-2021 HR-V, 2018-2020 Fit, 2020-2022 CR-V Hybrid, 2017-2022 CR-V, 2017-2018, 2021 Civic Type R, 2017-2021 Civic hatchback, 2016-2020 Civic coupe, 2016-2022 Civic, 2017-2022 Accord Hybrid, and 2016-2022 Accord vehicles. The front passenger seat weight sensor may crack and short circuit, which can cause the air bags to deploy unintentionally during a crash.

Safety Consequence: Air bags that deploy unintentionally during a crash increase the risk of injury.
Manufacturer Remedy: Dealers will replace the seat weight sensors, free of charge. Owner notification letters were mailed July 7, 2026. Owners may contact Honda's customer service at 1-888-234-2138. Honda's numbers for this recall are BOL, WO9, OOA, WOM, XOH, NOC, POD, BOE, UOF, POB, EOG, AOI, QO8, TOJ, DO7, and SOK. This recall expands previous NHTSA recall number 24V064. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning May 29, 2026.

Pre-Purchase Inspection Checklist for 2021 Acura TLX

Before purchasing a used 2021 Acura TLX, perform the following targeted inspections based on reported federal defect patterns:

1. Cold Start & Idle Diagnostics

Scan the OBD-II port under the dash for pending freeze-frame codes (e.g. P0300 misfires, P0087 fuel rail pressure, P0420 catalytic efficiency).

2. Transmission Shift Quality Audit

Test vehicle at low-speed stop-and-go and highway merges. Check for delayed reverse engagement or gear shift shudder between 2nd and 3rd gears.

3. Federal Recall Completion Check

Verify that all 4 NHTSA safety recall campaigns have been performed by an authorized dealership using the VIN.

4. Electrical & Infotainment Drain Check

Ensure the instrument cluster, center screen, and auxiliary charging ports operate with stable 12.0V–14.4V alternator voltage.

Frequently Answered Questions

Defect & Reliability Q&A: 2021 Acura TLX

Is the 2021 Acura TLX a reliable used car?

The 2021 Acura TLX earns a 4.1/10 MazicBay Reliability Index based on 65 federal owner reports. Vehicles maintained under factory service schedules exhibit strong longevity past 150,000 miles.

What is the most frequent defect reported on the 2021 Acura TLX?

The leading complaint category is Transmission Hesitation, Hard Shifting & Slipping Reports, with a median failure point around 55,300 miles (IQR: 23,16677,500 mi).

Are there free recall repairs available for the 2021 Acura TLX?

Yes, the NHTSA records 4 safety recall campaign(s) for this model year. All safety recalls are performed 100% free of charge by authorized franchise dealerships regardless of vehicle warranty status.

2021 Acura TLX Owner Maintenance & Equipment CenterVerified battery BCI group sizes, oil sump capacities, and tested scan tools.
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