1992 INFINITI M30

Typical onset: 80,000-150,000 mi

Symptoms: Strawberry milkshake appearance in coolant overflow or radiator, Transmission slipping or delayed engagement after coolant contamination, Transmission failure within days if coolant mixes with ATF

Fix: The integral cooler inside the radiator corrodes and allows coolant into the transmission. Preventive fix: replace radiator and external trans cooler (4-5 hours). If contamination occurred, full transmission rebuild or replacement required (12-16 hours total with R&R). This is a known Nissan-wide issue of this era.

Estimated cost: $800-1,200 preventive; $3,500-5,500 after contamination with rebuild

Typical onset: 120,000-180,000 mi

Symptoms: Heavy rod knock on cold starts or under load, Excessive oil consumption (more than 1 qt per 500 miles), Blue smoke from exhaust on deceleration, Low oil pressure at idle when warm

Fix: VG30E engines with neglected oil changes develop worn main/rod bearings and collapsed piston rings. Requires short block replacement or full rebuild with pistons, rings, bearings, and machine work (25-35 hours labor). Head gaskets typically done simultaneously if cracked open.

Estimated cost: $4,500-7,500

Typical onset: 100,000+ mi

Symptoms: Hard starting after sitting overnight, Raw fuel smell in engine bay, Rough idle and hesitation during acceleration, Visible fuel weeping at injector o-rings

Fix: 30-year-old rubber fuel hoses, injector o-rings, and seals crack and leak. Fuel filter clogs from tank sediment. Full service includes fuel filter, all injector seals, pressure regulator refresh, and fuel line inspection (3-4 hours). Sometimes requires injector replacement if internally fouled.

Estimated cost: $600-1,200

Typical onset: 80,000-140,000 mi

Symptoms: Clunking when shifting from park to drive, Excessive engine movement visible under acceleration, Vibration at idle that improves with RPM, Banging noise over bumps from driveline

Fix: Rubber mounts collapse with age. Transmission mount is the usual culprit but all engine mounts should be inspected. Replace all four mounts as a set (3-4 hours). Hydraulic-filled mounts are OEM spec but expensive; solid aftermarket available.

Estimated cost: $450-800

Symptoms: Intermittent no-start when humid or wet, Misfires and stumbling under load, Check engine light with multiple cylinder misfire codes, Carbon tracking visible inside distributor cap

Fix: The VG30E uses a distributor with cap/rotor that corrode in coastal or humid climates. Replace cap, rotor, plug wires, and spark plugs as a set. Check and adjust mechanical timing if drifted (2 hours total). Ignition coil occasionally fails as well.

Estimated cost: $350-600

Typical onset: 100,000-160,000 mi

Symptoms: Power steering fluid puddles under front center of car, Groaning noise when turning at low speed, Steering becomes progressively heavier, Visible fluid weeping at inner tie rod boots

Fix: Rack seals deteriorate and leak. Rebuilt or new rack required with alignment (4-5 hours). Used racks are plentiful but condition varies. Flush system after replacement to remove debris.

Estimated cost: $800-1,400