1993 MAZDA MX-5 MIATA

Typical onset: 80,000-150,000 mi or 25+ years regardless of miles

Symptoms: Oil weeping from timing cover area, Oil drips visible on ground after parking, Oil spray pattern on underside of hood when driving, Gradual oil consumption increase

Fix: Front main seal replacement requires timing belt removal, crank pulley extraction (often seized), and potentially woodruff key replacement if damaged. Plan 4-6 hours labor. While you're in there, replace cam seal, valve cover gasket, and CAS o-ring—they all fail around the same time. The crank bolt is torqued to 116-123 ft-lbs and frequently rounds off if prior owner overtightened.

Estimated cost: $450-750

Typical onset: Can occur anytime after 60,000 mi, often triggered by improper belt service

Symptoms: Sudden no-start with cranking but no compression, Timing jumps erratically, Metallic rattling from front of engine, Crank pulley wobbles or spins freely

Fix: The 1.6L crank nose is shorter and weaker than the 1.8L design. The woodruff key shears or the keyway wallows out, causing the timing gear to slip. Only real fix is crank replacement or specialized welding/pinning repair. Expect 12-16 hours labor for crank swap including disassembly, machine work, and reassembly. Some shops refuse the job and recommend engine replacement or 1.8L swap instead.

Estimated cost: $2,500-4,500

Typical onset: 60,000-120,000 mi

Symptoms: Oil pooling in spark plug tubes (fouling plugs/coil packs), Burning oil smell in cabin with heater on, Oil residue on valve cover perimeter, Oil seeping around cam angle sensor

Fix: Straightforward 2-3 hour job. Remove valve cover, clean mating surfaces thoroughly (old gasket material loves to stick), replace cork/rubber gasket with OEM or quality aftermarket. Replace all four spark plug tube seals and the CAS o-ring simultaneously—they're 30 years old and will leak within months if you skip them. Use half-moon seals on timing cover side, not RTV.

Estimated cost: $250-450

Typical onset: Original parts fail 80,000-130,000 mi; age-related failure regardless of miles after 20+ years

Symptoms: Overheating in traffic or spirited driving, Coolant seepage at radiator end tanks, Weeping from water pump weep hole, Collapsed or cracked rubber hoses, Sweet coolant smell in cabin

Fix: The plastic radiator end tanks crack and the core corrodes. Budget 2-3 hours for radiator replacement. Water pump typically fails at 80k-100k; do it with timing belt service (add 1 hour to belt job). Replace ALL rubber coolant hoses if original—they collapse internally and cause phantom overheating. Thermostat housing o-rings also leak. Smart play: complete cooling refresh all at once with timing belt.

Estimated cost: $600-1,200

Typical onset: 100,000-180,000 mi

Symptoms: Shifter feels loose, rubbery, or vague, Difficulty engaging 1st/2nd when cold, Grinding into reverse, Gear oil leaking from shifter turret area, Popping out of 5th gear under load

Fix: The shifter turret seals dry out and leak, causing vague feel. Rebuild kit with new boots, springs, and detent components takes 3-4 hours. If it's popping out of 5th, the synchro sleeve is worn and you're looking at a full transmission rebuild (10-12 hours) or swap. CWP (cam, welch plug) seal at rear of trans is notorious for leaking—needs trans removal, 5-6 hours labor.

Estimated cost: $400-800 for turret; $1,500-2,200 for trans rebuild

Typical onset: Can start as early as 50,000 mi with poor maintenance; universal on neglected engines

Symptoms: Loud ticking from valve cover at idle, quiets with RPM, Worse when cold, may improve when warm, Single or multiple ticks audible from driver's seat, No performance loss in most cases

Fix: The B6-ZE hydraulic lifters wear or get gummed up from old oil. Try a high-detergent oil flush first—surprisingly effective on marginal cases. If persistent, lifter replacement requires valve cover removal, cam removal, and shim-under-bucket valve adjustment (2.5-3.5 hours). You'll need shims on hand and feeler gauges. Some techs replace all 16 lifters preventatively; others chase the noisy ones. OEM lifters are $15-25 each.

Estimated cost: $450-700