2015-2025 Acura TLX Problems: 15 Known Issues

The ZF 9HP 9-speed automatic transmission paired with the V6 in first-gen TLX models exhibits a pronounced shudder during low-speed acceleration and harsh shifts between 2nd and 3rd gear. The torque converter lockup strategy causes a noticeable vibration between 25-45 mph that worsens in warm weather.

Roughly 8,354 2015 Acura TLX vehicles (2WD and 4WD) left the factory with insufficiently crimped connections in the transmission wire harness. The intermittent connection causes the transmission control system to drop the car into neutral without driver input - typically at highway speed. Owners describe the car losing all drive mid-traffic, dropping into limp mode, and being unable to re-engage a gear until the ignition is cycled. Honda recalled the population under 16V640000 (Honda internal number KC2) with a recall start of January 13, 2017. Notably, unexpected neutral-shift complaints continue on 2015-2017 TLX beyond the recalled VIN range, described in NHTSA filings as 'transmission randomly shifted into neutral' and 'vehicle went into limp mode and shifted into neutral', so a car outside the recall can still exhibit the symptom from a related connector or transmission control fault.

On 2015 TLX models with the 3.5L V6 and the ZF-sourced 9-speed automatic, the transmission's parking pawl may be contaminated during assembly, or the park rod may become dislodged or break. The shift indicator reads PARK and the driver walks away, but the park lock never mechanically engaged - the car can roll away. Honda recalled approximately 9,392 2015 TLX V6 vehicles in both 2WD and SH-AWD form under 14V779000, with the remedy being inspection and, where the defect is found, replacement of the entire transmission. This is a mechanical park-lock defect and is distinct from the well-known 9-speed harsh-shift and shudder behavior: it can occur on a car that shifts perfectly. It does not apply to the 2.4L four with the 8-speed dual-clutch, which uses a different park mechanism.

Certain second-generation TLX vehicles were built with the fuel filler neck improperly welded to the fuel tank. The defective weld can allow fuel to leak from the tank assembly, and a fuel leak in the presence of an ignition source is a fire risk. Honda recalled a small population of 2021-2023 Acura TLX (about 167 vehicles) under 24V950000 with a full fuel tank assembly replacement as the remedy. Because the leak originates at the filler neck joint, owners typically smell raw fuel around the right rear of the car or see wetness or staining near the filler area, most noticeably after filling the tank completely.

The Denso in-tank low-pressure fuel pump module used across the first-generation TLX fails, causing hesitation, hard starting and complete engine stall - often at speed or mid-turn. Two distinct defect mechanisms were recalled: particulates in fuel adhering to internal pump components and degrading pump output (19V060000, covering 2015-2019 TLX with the 3.5L V6), and a pump impeller that absorbs fuel, deforms and binds against the pump housing (21V215000 for 2019-2020, expanded by 23V858000, a 2013-2023 Honda/Acura campaign that covers 2015-2020 TLX). Owners report repeated stalls even after one recall repair, and a documented cascade in which a failed low-pressure pump is replaced but the high-pressure pump fails soon after because dealers replace only one component - producing P0087 low fuel rail pressure. Recall parts availability has been a recurring complaint, with owners waiting months.

2015-2020 first-generation TLX models built with the J35 3.5L V6 suffer a manufacturing defect in the connecting rod bearings. Improperly ground crankshaft crank pins (crowned or convex, out of specification) cause the rod bearing to wear, spin and eventually seize. Owners report a developing knock or tick that escalates to catastrophic failure - thrown rods punching through the block, holes in the oil pan and fractured crankshafts - frequently with no warning light before the failure. NHTSA complaint volume for this failure mode is the single largest category on the nameplate: the database lists about 97 engine complaints for the 2015 model year and 41-45 each for 2016, 2018 and 2019, many describing this failure. Honda issued safety recall 23V751000 in late 2023 covering 2015-2020 Acura TLX (and related J35 applications). Multiple owners report the failure recurring on the recall-installed replacement engine, and widespread recall-parts backorders left cars immobilized for months. This is a V6 failure only - it does not apply to the K24 2.4L four, nor to either engine in the second-generation TLX.

The base second-generation TLX uses a 2.0L turbocharged four with a front-mounted air-to-air intercooler. In humid, rainy or cold-and-damp conditions, water vapor condenses inside the intercooler and charge piping, pools, and is then slugged into the intake on a throttle transition. The result is a sudden multi-cylinder misfire, a stumble or hard bucking under acceleration, and in many cases a drop into limp mode with reduced power until the ignition is cycled. NHTSA complaints on the 2021 TLX describe a flashing check engine light and loss of power when accelerating in rain, with one dealer attributing it to 'water getting into the car's intercooler for the turbo', and Acura Service Bulletin 20-053 lists humid intake air condensing during steady driving as the possible cause. This is specific to the turbocharged four - the Type S 3.0T uses a different charge-air layout, and the first-generation naturally aspirated engines have no intercooler at all.

Second-generation TLX models were built with the brake pedal pivot pin not secured properly. The pin can migrate, letting the pedal shift out of its correct position on the pedal bracket. When that happens the driver's input no longer translates properly to the master cylinder and braking can be prevented or badly reduced. Honda recalled 2021-2025 Acura TLX alongside 2023-2025 Acura MDX and 2023-2025 Honda Pilot under 25V391000, with owner letters mailed July 29, 2025 - a campaign covering roughly a quarter-million vehicles. Independent of the recall, NHTSA complaints on 2021+ TLX cars describe a sticky or inconsistent brake pedal and pedal-feel changes that dealers initially dismissed as 'working as designed' before the recall issued.

The 2021–2025 TLX Type S and Type S PMC use a fixed front Brembo brake system whose performance-oriented pad compound can squeal during light braking and wear unevenly if pad-retaining hardware or contact points corrode. This does not apply to the A-Spec brake system.

On the second-generation (UB5) TLX with SH-AWD, the splined interface between the 10-speed transmission output and the power transfer unit (transfer case) strips or shears. Owners describe a loud pop, bang or clunk from underneath, after which the car silently reverts to front-wheel drive - critically, with NO dashboard warning light and no stored DTC, so the driver often does not know AWD is gone until the car loses traction on a slippery surface or a technician spots it at a service. Many cases are preceded by a fluid leak from the transmission-to-differential seal or brown sludge in the fluid. NHTSA opened defect petition DP26001 on March 6, 2026 covering loss of all-wheel drive in 2021-2023 Acura TLX (and 2022-2023 MDX) due to transmission-to-PTU spline failure, and denied the petition on August 4, 2026 after reviewing 62 owner complaints, saying the loss of SH-AWD does not cause a loss of motive power or vehicle control; the denial is not a finding that no defect exists. Complaint mileages span roughly 8,000 to 100,000 miles, including many inside the factory warranty. Owners report the replacement PTU is already on its third revision (part 29000-5YK-070) with no TSB issued, and that parts sit on national backorder for weeks. Documented repair costs range from about $5,000 to $19,000 because the transmission usually has to be replaced along with the transfer case. This is a UB5 SH-AWD failure - it is not the first-generation SH-AWD rear drive unit.

The front passenger seat weight sensor that feeds the occupant classification system cracks and short circuits. Two separate campaigns cover TLX: 24V064000 (2020-2021 TLX, sensor cracks so the system fails to suppress the passenger airbag as intended) and the later, broader 26V332000 (2018-2021 and 2023 TLX, cracked sensor short-circuiting such that airbags can deploy unintentionally). The second campaign expands the first and describes the same defect: a passenger airbag that is not suppressed when it should be, so it can deploy in a crash when it should stay off. Owners commonly notice the passenger airbag OFF indicator behaving erratically or staying lit with an adult in the seat. Complaint filings for 2021 note the replacement sensors were unavailable for seven months or more with no ETA from the manufacturer.

The AcuraWatch front camera and millimeter-wave radar produce false Collision Mitigation Braking System activations - the car brakes hard, sometimes to a full stop, with no vehicle or obstacle ahead. NHTSA filings on the 2018 TLX describe the 'frontal crash mitigation feature suddenly slammed the brakes on fully to a complete stop', and 2021 filings include an owner rear-ended after a false activation. The same sensor failures produce a signature cascade of dashboard warnings - CMBS Problem, ACC Problem, LKAS Problem and Road Departure Mitigation all illuminating together - because a single failed front camera or an obstructed radar disables every function that depends on it. Common triggers include rain, snow, spray, a bug-splattered or fogged camera area, low sun angle, and shadows or overhead signage. First-generation cars concentrate the failures in the windshield-mounted camera; second-generation (2021+) cars add radar-obstruction messages in inclement weather. Owners also report the systems cannot be conveniently disabled, and that Acura roadside gave instructions for the wrong model year.

The dual-screen infotainment system in first-generation TLX models suffers from severe lag, random freezes, and full system crashes requiring a restart. The upper navigation screen and lower touchscreen frequently lose sync, with Bluetooth audio dropping mid-stream and the backup camera failing to display.

A February 2025 Acura investigation concerned adaptive-damper warnings on US-market 2021–2023 TLX Advance and 2021–2025 Type S vehicles. It lists rear stroke-sensor upper- and lower-limit faults. The parts-collection request expired in February 2025 and is not a recall or a current repair authorization. A-Spec models are not included.

P-AWS is TLX-specific hardware: two independent electric actuators toe the rear wheels for low-speed agility and high-speed stability, fitted to first-generation front-drive TLX models (the SH-AWD cars use the rear drive unit instead). The actuators fail - electrically and mechanically - and when one goes the rear toe can be left misaligned. Owners report sudden pull or wander, a car that tracks crooked, and a system fault that limits the car's usable speed. The failure is expensive because the actuators are not serviceable parts and are replaced as assemblies: an NHTSA complainant on a 2020 TLX documented a $9,210 quote to replace two rear wheel steering actuators, calling it 'a known issue'. Related 2018 filings describe P-AWS actuator failures causing sudden misalignment and limiting the car to about 50 mph. There is no recall covering this failure.