1997 MAZDA RX-7

Typical onset: 60,000-100,000 mi

Symptoms: Hard starting when warm, Loss of power under boost, Excessive oil consumption (more than 1 qt per tank), Rough idle with misfires, Failed compression test (under 6.5 kg/cm² per rotor face)

Fix: Full rotary rebuild required—remove engine, disassemble housings, replace apex seals, side seals, corner seals, bearings, all gaskets. Typical rebuild takes 20-30 labor hours depending on shop familiarity with rotaries. Must be done by rotary specialist or expect comebacks.

Estimated cost: $4,000-7,000

Typical onset: 70,000-120,000 mi

Symptoms: Loss of top-end power above 4500 RPM, Smoke on boost (oil-fed turbos), Rattling or whistling under acceleration, Overboost / underboost codes, Excessive shaft play on primary or secondary turbo

Fix: Sequential twins are complex—primary and secondary turbos fail independently. Primary more common. Replace turbos, gaskets, oil feed lines, coolant lines. Also inspect precontrol and wastegate solenoids. Engine-out job on secondary turbo. 12-18 hours labor for both.

Estimated cost: $2,200-4,500

Symptoms: Coolant temps exceeding 200°F under normal driving, Heater blowing cold at idle, Bubbling overflow tank, Failed AST (air separator tank) allowing air pockets, Water pump weeping coolant from weep hole

Fix: Rotaries are heat-sensitive—cooling system failure kills apex seals fast. Replace AST, radiator (often clogged internally), water pump, thermostat, all hoses. Bleed system meticulously using factory procedure with front end elevated. 6-10 hours labor depending on radiator choice.

Estimated cost: $1,200-2,500

Typical onset: all ages

Symptoms: Erratic idle, surging at light throttle, CEL with P0400-series codes (EGR/emissions), Sequential turbo not transitioning (stuck in primary), Limp mode / overboosting, Hissing sounds from engine bay

Fix: Miles of vacuum lines control turbos, emissions, idle. All rubber lines crack with age and heat. Replace entire vacuum system with silicone—rats nest elimination common upgrade. Map every line during removal. 8-12 hours labor if done thoroughly.

Estimated cost: $600-1,200

Typical onset: 80,000-140,000 mi

Symptoms: Grinding into 2nd gear when cold, Difficult or balky 3rd gear engagement under load, Gear pop-out under deceleration, Crunching on quick 2-3 shift

Fix: 5-speed manual (not 6-speed R1/R2) develops worn synchros from aggressive shifting. Trans-out rebuild with replacement synchros, shift forks inspection, new bearings. 10-14 hours labor—must drop exhaust, driveshaft, shifter assembly.

Estimated cost: $1,800-3,200

Typical onset: 60,000-100,000 mi

Symptoms: Clunking over bumps from rear, Vague rear-end feel under hard cornering, Excessive rear toe change under acceleration/braking, Visible cracking or tearing of subframe bushings on inspection

Fix: Rubber subframe bushings deteriorate and allow unwanted movement. Replace all four subframe bushings (often upgrade to polyurethane). Subframe must be dropped—requires alignment afterward. 4-6 hours labor.

Estimated cost: $500-900

Typical onset: 80,000-120,000 mi

Symptoms: Stumbling or lean misfire at high RPM under boost, Fuel pressure dropping below 40 psi, Hard starting after sitting, Car cuts out mid-pull then recovers, CEL with lean codes (P0171/P0174)

Fix: Stock fuel pump weak by modern standards—any mods push it over edge. Also check fuel filter (often neglected), fuel pressure regulator, and pulsation damper. Lean condition kills rotaries fast. Pump replacement 3-4 hours, drop tank or access via rear seat.

Estimated cost: $400-800