2006 MAZDA RX-8

Typical onset: 60,000-100,000 mi

Symptoms: Hard cold starts or extended cranking, Loss of power especially at high RPM, Poor fuel economy dropping below 16 mpg, Excessive blue smoke on startup, Compression test showing under 6.5 kg/cm² on any rotor face

Fix: Complete engine rebuild or reman engine swap. Rebuild takes 20-30 hours including removal and reinstallation. Most owners opt for Mazda reman or used JDM engine due to specialized knowledge required. This is a when-not-if issue on these engines.

Estimated cost: $4,000-7,000

Symptoms: Won't start after short trips or being shut off warm, Fouled spark plugs with carbon buildup, Strong fuel smell from exhaust when cranking, Requires pull-fuses-and-crank deflood procedure

Fix: Immediate fix is deflooding procedure (pull fuel pump fuse, hold throttle wide open, crank 10 seconds, reinstall fuse). Replace spark plugs and coils as preventive measure. Each coil takes 0.3 hours, plugs another 0.5 hours. Real solution is never shutting engine off cold and upgrading starter for faster cranking.

Estimated cost: $400-800

Typical onset: 30,000-60,000 mi

Symptoms: Misfires under load or at high RPM, Flashing check engine light, Rough idle, P0301/P0302 misfire codes for leading or trailing plugs

Fix: Replace all four coils and eight spark plugs as a set—never do just one. Leading and trailing coils are different parts. Takes 2 hours total. Aftermarket coils fail faster; use OEM Mazda or quality upgraded coils. Budget this every 30-40k miles.

Estimated cost: $600-900

Typical onset: 50,000-80,000 mi

Symptoms: P0420 catalyst efficiency code, Loss of power above 7000 RPM, Rattling from exhaust on startup, Overheating due to exhaust restriction

Fix: Rotary oil consumption kills cats prematurely. Requires removing entire exhaust system to access the cat integrated into midpipe. Book time 3-4 hours. Many owners go aftermarket midpipe with high-flow cat or test pipe where legal. OEM Mazda part is $1,800+ alone.

Estimated cost: $1,200-2,500

Typical onset: 80,000-120,000 mi

Symptoms: Clicking but no crank, Slow cranking especially when warm, Intermittent no-start requiring multiple key cycles

Fix: Starter takes abuse from flooding and compression cranking. Replacement is 2.5 hours labor. Upgraded high-torque starters exist and are worth the premium for flood resistance. Original Mazda starters barely meet spec for this engine.

Estimated cost: $500-800

Typical onset: 70,000-100,000 mi

Symptoms: Excessive vibration at idle, Clunking when shifting or during throttle transitions, Engine visibly sagging or tilted in bay

Fix: All four mounts deteriorate from rotary vibration. Front and rear take 1.5 hours each, transmission mount 1 hour, side mount 0.8 hours. Do them all at once—about 5 hours total with engine support. Polyurethane upgrades add NVH but last longer.

Estimated cost: $600-1,000

Typical onset: 100,000+ mi

Symptoms: Dying under hard acceleration or high RPM, Won't start when fuel tank below 1/4, Whining noise from rear seat area, Stumbling or cutting out at 8000+ RPM

Fix: Drop tank or remove rear seat access panel depending on model year. 2-3 hours labor. Mazda recalled some for pump issues but not all years covered. Use OEM pump—aftermarket units can't handle fuel starvation in corners on track days.

Estimated cost: $500-900