2018 ACURA RLX

Typical onset: 40,000-80,000 mi

Symptoms: Excessive oil consumption (1 quart per 1,000 miles or worse), Blue smoke from exhaust on startup or acceleration, Loss of power and rough idle as rings fail completely, Metal shavings in oil, low oil pressure warning, Connecting rod knock or bearing failure once oil starvation occurs

Fix: This is a known Honda/Acura J35 V6 defect from 2016-2019 production. Piston rings made with substandard materials fail prematurely, causing oil consumption that leads to bearing damage. Fix requires complete engine rebuild or short block replacement. Labor alone is 18-24 hours for engine removal, disassembly, machining (if salvageable), new pistons, rings, bearings, gaskets, and reassembly. Many shops recommend full short block replacement to avoid liability. Some owners have obtained goodwill assistance from Acura even outside warranty.

Estimated cost: $8,000-14,000

Symptoms: Engine stalls without warning while driving, No-start condition, engine cranks but won't fire, Rough running or hesitation under load, Check engine light with fuel pressure codes

Fix: Denso fuel pump impeller can crack and fail due to manufacturing defect. This recall affects thousands of Honda/Acura vehicles from 2018-2020. Dealer will replace fuel pump assembly free of charge under recall. If you're buying used, verify recall completion via VIN check. Non-recall fix requires fuel tank drop and pump replacement, roughly 2.5-3 hours labor.

Estimated cost: $0 (recall) or $800-1,200 if out-of-pocket

Typical onset: 60,000-100,000 mi

Symptoms: Red transmission fluid pooling under vehicle, Transmission overheating warning or slipping, Fluid level drops rapidly, Hard shifts or delayed engagement when fluid gets low

Fix: The oil cooler lines (running from transmission to radiator-mounted cooler) develop leaks at crimp connections or from road debris damage. Requires replacement of lines and often the external ATF filter. The 9-speed auto (standard RLX) or hybrid transaxle both route fluid externally. Labor is 2-3 hours depending on access and whether radiator needs partial removal. Always replace ATF and filter during this job.

Estimated cost: $600-1,000

Typical onset: 70,000-120,000 mi

Symptoms: Clunking noise when shifting from Park to Drive or Reverse, Excessive vibration at idle in Drive, Harsh engagement when accelerating from stop, Visible engine movement when applying throttle in park

Fix: The front transmission mount (engine side) uses fluid-filled rubber that deteriorates faster on the RLX due to weight and torque characteristics of the V6. Hybrid models sometimes see dual failures (front and rear mounts) due to added electric motor mass. Replacement is straightforward but requires supporting the engine/trans during swap. 1.5-2.5 hours labor per mount. Inspect all mounts if one fails—they tend to go together.

Estimated cost: $400-700 per mount

Typical onset: 100,000-150,000 mi

Symptoms: Reduced electric-only range, IMA warning light on dash, Engine running more frequently than normal, Decreased fuel economy (MPG drops significantly), Battery thermal management fan runs constantly

Fix: The RLX Sport Hybrid uses a lithium-ion battery pack with typical 10-year/150k-mile life expectancy. Individual cell failures trigger IMA warnings. Acura warranty covers 8yr/100k in most states, longer in CARB states. Replacement requires full pack swap—not individually serviceable cells. Labor is 4-6 hours due to rear seat and cargo area disassembly. Reconditioning services exist but reliability is unproven long-term.

Estimated cost: $4,000-6,500 (remanufactured) or $8,000+ (new OEM)

Symptoms: Touchscreen becomes unresponsive randomly, System reboots during drive (screen goes black, restarts), Navigation crashes or loses GPS signal, Audio cuts out intermittently, Backup camera fails to display

Fix: Software glitches in the 2018 model-year AcuraLink system are notorious. Dealers can perform software updates (TSB 18-048) but many owners report recurring issues. Some cases require complete head unit replacement if hardware fails. Labor is 1-2 hours for diagnosis and programming, 3-4 hours for full head unit R&R. This doesn't affect driveability but kills resale value and owner satisfaction.

Estimated cost: $200-400 (software update) or $2,000-3,000 (head unit replacement)