The 2004 TSX is Honda's K24A2 engine in a well-handling chassis, but suffers from two major issues: third-gear transmission failure and catastrophic engine oil consumption leading to bearing/piston failure. When maintained properly and if it escaped these grenades, it's a solid platform.
Third-Gear Transmission Failure (Automatic Only)
Common · high severityTypical onset: 80,000-140,000 mi
Symptoms: Harsh 2-3 or 3-4 shifts, flare on upshift, Slipping in third gear under moderate throttle, Transmission fault codes P0731, P0732, Complete loss of third gear, stuck in limp mode
Fix: Third-gear clutch pack burns out due to inadequate pressure from worn valve body. Requires transmission removal, full rebuild with updated clutches and valve body. 8-12 labor hours depending on shop efficiency. Many owners opt for reman unit due to core availability.
Estimated cost: $2,800-4,200
Excessive Oil Consumption / Piston Ring Failure
Common · high severityTypical onset: 100,000-180,000 mi
Symptoms: Burning 1+ quart per 1,000 miles, Blue smoke on startup or acceleration, Fouled spark plugs, misfires (P0300-P0304), Rod knock or bearing noise if oil starvation occurs, Low oil pressure warning
Fix: K24A2 piston rings seize in grooves due to oil coking, especially with extended drain intervals. Requires engine removal, full teardown, rebore or hone, new pistons, rings, bearings. 18-24 labor hours. Many techs recommend short-block or used engine swap at this mileage due to labor cost vs value.
Estimated cost: $3,500-6,500
Power Steering Hose Leaks
Common · medium severityTypical onset: 90,000-150,000 mi
Symptoms: Power steering fluid puddles under engine bay, driver side, Whining or groaning on lock-to-lock turns, Low fluid warning or heavy steering feel, Fluid spraying onto exhaust, burning smell
Fix: High-pressure hose from pump to rack deteriorates, develops pinhole leaks or splits at crimps. Hose replacement requires removing splash shields and working around AC lines. 2-3 labor hours. OEM hose strongly recommended over aftermarket due to pressure rating.
Estimated cost: $350-550
Transmission Oil Cooler Line Corrosion
Occasional · medium severityTypical onset: 110,000-160,000 mi
Symptoms: ATF dripping from radiator area or undercarriage, Low transmission fluid, delayed engagement, Pink fluid mixing with coolant (cooler internal leak), Transmission overheating
Fix: Steel lines to radiator-mounted cooler rust through, especially in salt states. External leaks need line replacement; internal leaks require radiator replacement plus fluid flush of both systems. External repair: 2-3 hours. Internal contamination adds major cost due to transmission damage risk.
Estimated cost: $400-900
Motor Mount Failure (Transmission Mount Primarily)
Common · low severityTypical onset: 80,000-130,000 mi
Symptoms: Clunk or thud on acceleration or deceleration, Vibration at idle in Drive, Excessive engine movement visible during throttle blips, Shifter vibration
Fix: Transmission mount (upper rear) and lower front mount tear due to hydraulic fluid leakage and age. Transmission mount requires supporting transmission from below, 1.5-2 hours. Front mount another 1-1.5 hours. Most techs do both simultaneously.
Estimated cost: $400-700
Fuel Filter Clogging (High-Mileage)
Occasional · low severityTypical onset: 150,000+ mi
Symptoms: Hesitation or stumble under hard acceleration, Long crank before start, Fuel pressure drops under load, P0171/P0174 lean codes in severe cases
Fix: Inline filter clogs with sediment, especially if tank has never been dropped. Filter is under vehicle near tank. 1 hour labor, but often coincides with fuel pump replacement decisions on higher-mileage cars.
Estimated cost: $150-250
Tail Light Circuit Board Corrosion
Occasional · low severitySymptoms: One or more tail light functions inoperative, Intermittent tail/brake light operation, Bulb replacement does not fix issue, Moisture visible inside tail light housing
Fix: Water intrusion corrodes circuit board contacts inside tail light assembly. Affected by recall but many units still fail post-repair. Requires tail light assembly replacement. 0.5-1 hour per side.
Estimated cost: $200-400
Buy a manual-transmission example under 100k miles that doesn't burn oil, or walk away — the automatic and oil-consumption issues are financial grenades that exceed the car's remaining value.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.