2021 Acura RDX Complaints

ELECTRICAL SYSTEM,UNKNOWN OR OTHER,SERVICE BRAKES — Filed 08/19/2026

Two low-speed sudden unintended acceleration events while parking a 2021 Acura RDX. Incident 1 (July 2026): While parking at low speed, the car unexpectedly surged forward. Flew up the curb and hit a restaurant window, causing massive undercarriage damage. Active braking did not help and seemed to make acceleration worse. It only stopped when it wanted to. Incident 2 (August 2026): Two weeks after getting the car back from repairs, under identical low-speed parking conditions, a second sudden acceleration event occurred. Slamming on the brakes did nothing. It stopped after scraping a car wash vacuum pole, destroying the entire passenger side. Prior to these, the car exhibited erratic safety software behavior, including multiple phantom braking incidents where it slammed on its brakes violently with no obstacles present. I bought the car Certified Pre-Owned two years ago. The dealership repaired a known "popping sound" from the panoramic sunroof frame three times. This required extensive cabin/pillar teardown work, which may have disturbed internal wiring harnesses or grounding points linked to the electronic throttle control system. In both events, it felt like an uncontrolled amusement park ride—the engine loudly revving and taking over with zero driver control. I initially assumed pedal confusion during the first crash, but since it happened again under identical circumstances, there is clearly a systemic electronic/software defect in the Throttle Actuator or Powertrain Control Module. The vehicle is at an insurance network body shop awaiting forensic evaluation of the throttle system, pedal sensors, and a Bosch EDR black box download.

FUEL/PROPULSION SYSTEM — Filed 07/06/2026

Fuel Pump is having to be replaced. I have had issues accelerating and my car also stalled once on the freeway. It put me in a dangerous situation and I almost got in an accident because my speed quickly decreased. The same part was recalled on the previous year’s model.

POWER TRAIN — Filed 07/09/2026

I own an Acura RDX that experienced a sudden failure of the transfer case. Prior to the failure, there was little or no warning that a major drivetrain component was about to fail. When the transfer case failed, the vehicle lost its normal all-wheel-drive operation and required expensive repairs. I believe this is a safety defect because the transfer case is a critical drivetrain component. A sudden failure can reduce traction and vehicle control, especially when driving at highway speeds or on wet, snowy, or icy roads. Drivers may not expect the loss of power to the rear wheels, which could increase the risk of skidding, loss of stability, or being unable to safely accelerate into traffic or avoid a hazard. In addition, there are numerous reports from other Acura RDX owners describing similar transfer case failures, suggesting this may not be an isolated incident but a recurring problem. A critical drivetrain component should not fail prematurely under normal use without adequate warning. I believe this issue warrants investigation because it has the potential to affect vehicle safety and place drivers and passengers at unnecessary risk.

POWER TRAIN — Filed 07/09/2026

I own an Acura RDX that experienced a sudden failure of the transfer case. Prior to the failure, there was little or no warning that a major drivetrain component was about to fail. When the transfer case failed, the vehicle lost its normal all-wheel-drive operation and required expensive repairs. I believe this is a safety defect because the transfer case is a critical drivetrain component. A sudden failure can reduce traction and vehicle control, especially when driving at highway speeds or on wet, snowy, or icy roads. Drivers may not expect the loss of power to the rear wheels, which could increase the risk of skidding, loss of stability, or being unable to safely accelerate into traffic or avoid a hazard. In addition, there are numerous reports from other Acura RDX owners describing similar transfer case failures, suggesting this may not be an isolated incident but a recurring problem. A critical drivetrain component should not fail prematurely under normal use without adequate warning. I believe this issue warrants investigation because it has the potential to affect vehicle safety and place drivers and passengers at unnecessary risk.

POWER TRAIN — Filed 07/09/2026

I own an Acura RDX that experienced a sudden failure of the transfer case. Prior to the failure, there was little or no warning that a major drivetrain component was about to fail. When the transfer case failed, the vehicle lost its normal all-wheel-drive operation and required expensive repairs. I believe this is a safety defect because the transfer case is a critical drivetrain component. A sudden failure can reduce traction and vehicle control, especially when driving at highway speeds or on wet, snowy, or icy roads. Drivers may not expect the loss of power to the rear wheels, which could increase the risk of skidding, loss of stability, or being unable to safely accelerate into traffic or avoid a hazard. In addition, there are numerous reports from other Acura RDX owners describing similar transfer case failures, suggesting this may not be an isolated incident but a recurring problem. A critical drivetrain component should not fail prematurely under normal use without adequate warning. I believe this issue warrants investigation because it has the potential to affect vehicle safety and place drivers and passengers at unnecessary risk.

POWER TRAIN — Filed 07/09/2026

I own an Acura RDX that experienced a sudden failure of the transfer case. Prior to the failure, there was little or no warning that a major drivetrain component was about to fail. When the transfer case failed, the vehicle lost its normal all-wheel-drive operation and required expensive repairs. I believe this is a safety defect because the transfer case is a critical drivetrain component. A sudden failure can reduce traction and vehicle control, especially when driving at highway speeds or on wet, snowy, or icy roads. Drivers may not expect the loss of power to the rear wheels, which could increase the risk of skidding, loss of stability, or being unable to safely accelerate into traffic or avoid a hazard. In addition, there are numerous reports from other Acura RDX owners describing similar transfer case failures, suggesting this may not be an isolated incident but a recurring problem. A critical drivetrain component should not fail prematurely under normal use without adequate warning. I believe this issue warrants investigation because it has the potential to affect vehicle safety and place drivers and passengers at unnecessary risk.

UNKNOWN OR OTHER — Filed 07/18/2026

While driving only at 35 miles per hour down the XXX in [XXX] my panoramic sunroof suddenly bursts. A loud pop sound. This would have popped all over my body if I didn’t have cover up. This is an extreme problem as someone can die from this. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ENGINE — Filed 07/13/2026

Vehicle lost all coolant and could be smelled. Vehicle was towed to dealership before it could overheat. Diagnosed with a cracked cylinder head at 88,000 miles. Vehicle has never been modified, tracked, nor has it ever overheated. All service has been performed on time and at Acura dealership since I purchased the vehicle brand new. Vehicle is still at dealership. I've researched and found many other owners experiencing the same problem with the crack occurring in the exact same spot on the cylinder head.

VEHICLE SPEED CONTROL,SERVICE BRAKES,ENGINE — Filed 07/15/2026

On or about XXX, my 2021 Acura RDX, with approximately 121,078 miles, suddenly displayed multiple dashboard warning lights and system-failure messages while I was driving. These included the check-engine light, Road Departure Mitigation System Problem, steering, stability-control, braking-assistance and other driver-assistance warnings. Earlier, the tire-pressure monitoring system had also indicated a malfunction even though the tire pressures were correct. The vehicle initially continued to drive and the conventional brakes appeared to function normally. However, it then began hesitating when I attempted to accelerate. The vehicle would eventually gain speed, but the initial hesitation created a serious safety concern when pulling into traffic or attempting to accelerate. The check-engine light remained solid while the vehicle was stopped but flashed whenever I began driving and accelerating again. No crash, fire or injury occurred. The vehicle had undergone a full diagnostic inspection approximately two weeks earlier, and I was informed that everything checked out properly. There were no known drivability problems before this incident, and the vehicle has been maintained according to the manufacturer’s recommended service schedule. The vehicle was subsequently inspected by Elite Acura, an authorized Acura dealership in [XXX]. The dealership confirmed a head-gasket failure and a problem with the rear differential left-side actuator. The dealer recommended replacing the head gasket, four spark plugs, coolant, oil and filter, as well as replacing the rear differential left-side actuator and changing the differential fluid. The estimated head-gasket repair was $5,391.46, and the estimated rear differential actuator and fluid service was $813.85. The dealer also recommended rear brake pads and rotors. The head-gasket and rear differential actuator problems were confirmed by the authorized Acura dealership. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN — Filed 11/01/2025

A transmission fluid leak has been identified emanating from the passenger side output shaft seal, located between the transmission and the transfer case. This issue pertains to 2019–2023 Acura RDX and TLX models equipped with SH-AWD, specifically at the interface where the transmission connects to the front transfer case, which is responsible for power distribution to the rear wheels. It appears that the fitment tolerances at this connection point are problematic, suggesting a potential engineering deficiency that warrants a manufacturer-funded resolution..