2002 MAZDA RX-7

Typical onset: 60,000-100,000 mi

Symptoms: Hard starting when hot, Loss of compression (rough idle, misfires), Heavy white/blue smoke on startup, Loss of power, especially under boost

Fix: Full rebuild required—disassembly, new apex/corner/side seals, bearings, oil control rings, housings resurfaced if scored. Typical rebuild is 25-35 labor hours plus machining. Most owners upgrade coolant routing, stronger apex seals (3mm), and oil metering delete with premix while it's apart.

Estimated cost: $4,500-8,000

Typical onset: 70,000-120,000 mi

Symptoms: Check engine light with boost control codes (P0035, P0243), No transition to secondary turbo above 4,500 RPM, Limp mode or overboost conditions, Hissing or rattling from turbo area

Fix: Vacuum solenoids fail, actuators seize, or rats nest vacuum lines crack. Diagnosis takes 2-3 hours due to complexity. Common fix is simplifying to single-turbo or non-sequential twins. OEM sequential repair is 8-12 hours labor including turbo removal and cleaning/replacing all actuators and lines.

Estimated cost: $1,200-3,500

Symptoms: Coolant temps exceeding 200°F under spirited driving, Heat soak after shutdown, Warped housings from repeated overheating cycles, AST (air separator tank) cap leaking or corroded

Fix: Factory cooling is marginal. Radiator, water pump, and thermostat must be perfect. Most need upgraded radiator (Koyo/CSF), rerouted coolant system (Pettit/RX7Store kit), and AST rebuild. Full preventive overhaul is 12-15 hours including new hoses, coolant reroute, and upgraded radiator.

Estimated cost: $2,000-3,500

Typical onset: 50,000-90,000 mi

Symptoms: Clunking on shifts or throttle lift, Vibration through chassis under load, Visible tearing or oil saturation of rubber mounts

Fix: OEM mounts are soft and fail quickly, especially on modified cars. Transmission mount replacement is 2 hours, differential mount another 2-3 hours. Most replace with polyurethane (70A durometer) for longevity at cost of NVH increase.

Estimated cost: $400-800

Typical onset: 80,000-130,000 mi

Symptoms: Lean condition under boost (wideband shows >13:1 AFR), Fuel pressure drop above 10 psi boost, Hard starting due to leaking injectors, Check engine light for lean codes

Fix: Primary and secondary fuel pumps weaken, filters clog, and 20-year-old injectors leak or stick. Tank should be dropped and cleaned (3 hours), both pumps replaced (4 hours total), and injectors cleaned or replaced (6 hours for rail removal and reinstall). Fuel filter is 1 hour but rarely done alone.

Estimated cost: $1,500-2,800

Symptoms: Erratic idle or stalling, Turbo control issues and boost spikes, Intermittent gauges or warning lights, Rats nest vacuum system leaks everywhere

Fix: The underhood vacuum and electrical systems are nightmares—brittle vacuum lines, corroded grounds, and aging connectors. Methodical replacement of all vacuum lines is 6-8 hours, cleaning all grounds another 3-4 hours. Most shops charge diagnostic time heavily here because issues are intermittent.

Estimated cost: $800-1,800