Honda is currently defending a cluster of class action lawsuits covering engine failures, transmission problems, phantom braking, peeling paint, idle stop no-restart failures, axle defects on the electric Prologue, and infotainment popping noises. One case, over the Automatic Idle Stop feature, has reached a proposed settlement offering repairs, extended warranties, and reimbursement. Others are still in early motion practice, one just ended in a jury verdict for Honda, and a federal safety investigation into the 3.5-liter V6 is running alongside the litigation. Here is where each case stands and which vehicles it covers.
3.5-Liter V6 Engine Failure Lawsuit
The largest engine case is Messenger v. American Honda Motor Co., Inc., filed January 12, 2026, in the Central District of California. The complaint alleges that crankshaft components in Honda’s 3.5-liter V6 were manufactured out of specification, producing increased friction, accelerated bearing wear, and a risk of engine seizure.1AboutLawsuits.com. Honda Class Action Lawsuit Recall Engine Defect
The lawsuit covers a wide range of Honda and Acura vehicles:
- 2016–2022 Honda Pilot
- 2017–2026 Honda Ridgeline
- 2018–2026 Honda Odyssey
- 2019–2025 Honda Passport
- 2014–2020 Acura RLX
- 2015–2020 Acura TLX
- 2016–2020 and 2022–2026 Acura MDX2Autoblog. Honda V6 Engine Class Action Lawsuit
Reported symptoms include abnormal engine noise often described as “rod knock,” loss of power, stalling on highways and in traffic, overheating, metal debris in the oil pan, and in some cases fires without warning.3CarComplaints.com. Honda 3.5-Liter V6 Engine Problems Lawsuit
Honda issued a recall in November 2023, updated in 2024, covering roughly 250,000 vehicles for out-of-spec crankshaft crank pins. The lawsuit alleges that recall was far too narrow, that it excluded many vehicles with identical engine components whose VINs fell outside the recall range, and that it failed to address broader design problems with the engine’s rotating assembly and operating temperatures. The plaintiff called it “halfhearted and unconscionable.”1AboutLawsuits.com. Honda Class Action Lawsuit Recall Engine Defect
Separately, on August 20, 2025, the National Highway Traffic Safety Administration opened Preliminary Evaluation PE25008 covering approximately 1.4 million vehicles with the 3.5-liter V6: the 2016–2020 Pilot, 2017–2019 Ridgeline, 2018–2020 Odyssey, 2016–2020 MDX, and 2018–2020 TLX. NHTSA said the connecting rod bearing failures it is examining appear distinct from the crankshaft defect addressed in the 2023 recall, and that Honda had denied warranty coverage for 173 newer complaints with similar symptoms.4Yahoo Autos. Honda Engine Investigation By mid-2026, over 3,000 engine failure incidents had been reported, including seven crashes or fires, with no injuries or fatalities. The investigation remains at the preliminary evaluation stage.5NHTSA. NHTSA Investigation PE25008
Honda filed motions to dismiss the amended complaint, set for hearing August 10, 2026, before Judge Stephen V. Wilson. No class has been certified.6PACER Monitor. Messenger v. American Honda Motor Co.
1.5L and 2.0L Turbo Engine Coolant Leak Lawsuit
A separate case, Alcantara v. American Honda Motor Co., Inc., was filed July 1, 2025, in the Central District of California. It alleges that Honda’s 1.5-liter and 2.0-liter turbocharged engines in 2016–2022 Civic, Accord, and CR-V models, along with the Acura RDX and TLX, contain a design defect that lets engine coolant seep through grooves on the cylinder head into the cylinders. The result, according to the complaint, is head gasket degradation, overheating, and sudden loss of power. Plaintiffs allege Honda knew about the defect, did not disclose it, and refused warranty coverage, leaving owners to pay for repairs.7Top Class Actions. Honda Class Action Alleges Defective Turbocharged Engines
Nine-Speed Transmission Lawsuit
Moore v. American Honda Motor Co., Inc., filed September 29, 2023, in the Northern District of California, targets the ZF 9HP nine-speed automatic transmission. The complaint alleges the transmission control module and powertrain control module are improperly calibrated, causing rough or delayed shifting, loud shifting noises, harsh gear engagement, sudden acceleration and deceleration, and sudden loss of power.8ClassAction.org. Honda Transmission Problems Lawsuit
Affected vehicles are the 2016–2022 Pilot, 2018–2019 Odyssey, 2019-present Passport, and 2020-present Ridgeline. The complaint acknowledges Honda has issued technical service bulletins about the symptoms but alleges dealer software updates only mask the problem. The case remains pending, with no class certification or settlement as of mid-2026.9HondaTransmissionLawsuit.com. Honda Transmission Lawsuit
Automatic Idle Stop Settlement (Claims Open)
This is the one active Honda case currently offering owners relief. In re Honda Idle Stop Litigation addresses a defect that allegedly prevents vehicles from restarting after the engine shuts off at a stop. The settlement class covers:
- 2015–2020 Acura TLX
- 2016–2020 Acura MDX
- 2016–2021 Honda Pilot
- 2019–2021 Honda Passport
- 2020–2021 Honda Ridgeline
Vehicles must be equipped with the NP0 engine and nine-speed transmission.10Settlement-Claims.com. Auto Idle Stop Settlement
The settlement provides three forms of relief. First, Honda is amending its service bulletins to drop the requirement that dealers verify the “no-restart” symptom before performing a free starter replacement during the warranty period. Second, 2015 Acura TLX owners get an additional 24 months of warranty beyond the original expiration for valve adjustment and starter replacement; 2016 TLX, MDX, and Pilot owners get an additional 18 months. Third, class members can file claims for past and future out-of-pocket costs tied to the no-restart issue, including starter and relay replacement, valve adjustments, and towing.
A Final Approval Hearing is scheduled for May 18, 2026. Claims for past expenses must be filed within 90 days of the final approval order; future costs must be submitted within 60 days of being incurred.11Settlement-Claims.com. Honda Idle Stop Settlement FAQ
Phantom Braking (CMBS) Cases
The long-running phantom braking case, Cadena v. American Honda Motor Co., Inc., alleged that the Collision Mitigation Braking System in 2017–2019 CR-V and 2018–2020 Accord vehicles misidentified objects and applied hard braking when no threat existed. The class covered more than 100,000 drivers across eight states.12HondaCMBSClassAction.com. Honda CMBS Class Action
The case went to trial. On April 17, 2026, the jury returned a verdict for Honda, finding that the CMBS in the affected vehicles was not legally defective.13CarComplaints.com. Honda Wins Phantom Braking Lawsuit Trial Post-trial motions are ongoing.14PACER Monitor. Cadena v. American Honda Motor Co.
A separate CMBS case, Sivakova v. American Honda Motor Company, Inc., covers the same system in the 2019–2022 Insight and 2019–2022 Passport. Honda has moved to dismiss, arguing the owner’s manuals warned buyers about potential false activations in certain road conditions.15CarComplaints.com. Honda CMBS Class Action Lawsuit
White Paint Peeling Lawsuit
Clemmens v. American Honda Motor Company, Inc. alleges that certain 2013–2025 Honda and Acura vehicles painted in specific whites suffer from a tri-coat paint defect causing peeling, delamination, bubbling, and flaking. Affected paint colors and models include:
- Acura MDX in White Diamond Pearl
- Honda Odyssey in White Diamond Pearl or Taffeta White
- Honda Pilot in Taffeta White
- Honda Fit in White Orchid Pearl or Bellanova White
- Honda HR-V in White Orchid Pearl or Bellanova White16CarComplaints.com. Honda White Paint Lawsuit Dismissed
Judge Otis D. Wright II dismissed the case in July 2025, ruling peeling paint was an aesthetic issue unrelated to the vehicle’s central function and that plaintiffs had not identified specific promotional materials they relied on. The plaintiffs amended. In a March 2026 ruling, Judge Wright reversed himself on the central-function question, accepting that paint failure could compromise structural integrity, and allowed fraud-based claims to proceed on the theory that Honda concealed the defects to induce purchases. The case is moving forward on California consumer protection claims.17CarComplaints.com. Honda White Paint Class Action Lawsuit
Honda Prologue Axle Lawsuit
Custer v. American Honda Motor Co., Inc., filed March 2, 2026, in the Eastern District of Pennsylvania, targets the electric Prologue SUV. The lawsuit alleges that 2024–2026 Prologue models have defective front drive CV axle assemblies with internal joint irregularities that produce clicking or ratcheting noises during turns, impair propulsion and steering response, and can lead to axle breakage and loss of vehicle control.18ClassAction.org. Honda Prologue Vehicles Equipped With Defective Axles
According to the complaint, Honda acknowledged the problem in an internal “Tech Line” publication but has only offered to replace defective axle parts with identical components, so failures recur. Some dealers have reportedly appraised affected Prologues at less than half of their original sticker price. The plaintiffs seek damages, a recall, and replacement with redesigned parts. No recall has been issued.19Lemberg Law. Custer v. American Honda Motor Co.
Infotainment Speaker Popping Lawsuit
Two overlapping cases target audio defects in Honda’s three-row vehicles. Fausto v. American Honda Motor Co., Inc., filed August 2024, alleges an electrical defect that causes speakers to emit loud, intermittent popping or crackling noises in the 2020–2022 Pilot, Passport, and Odyssey, excluding certain base trims.20ClassAction.org. Honda Infotainment System Defect Lawsuit A related case, Gonzalez v. American Honda Motor Co., covers similar vehicles and adds phantom braking allegations. The complaint alleges Honda has known about the defects since 2017 but has not provided a permanent fix.21Top Class Actions. Honda Class Action Alleges Infotainment Braking Defects
If Your Honda Is on One of These Lists
For most of these cases, no class has been certified and no money is available yet, so there is nothing to file. The exception is the idle stop settlement: if you own or leased a covered TLX, MDX, Pilot, Passport, or Ridgeline with the NP0 engine and nine-speed transmission, and you paid out of pocket for a starter or relay replacement, valve adjustment, or towing tied to a no-restart, you can submit a claim through the settlement website, and the extended warranty applies automatically to eligible model years. Keep repair invoices and dealer records for the other cases; if any of them settles or certifies a class later, prior documented repairs are typically the strongest basis for reimbursement.