1991–2002 INFINITI G20

Typical onset: 80,000-150,000 mi

Symptoms: Pink or milky transmission fluid (coolant mixing), Transmission slipping, delayed engagement, or complete failure, Overheating transmission, erratic shifting, Coolant level drops without visible external leaks

Fix: The steel cooler lines running to the radiator corrode internally, allowing coolant and ATF to mix. This destroys the automatic transmission within days if not caught. Requires replacing both cooler lines, flushing cooling system, and often full transmission rebuild or replacement. External cooler install recommended as preventive. Labor: 8-12 hours for trans R&R plus lines.

Estimated cost: $2,500-4,200

Typical onset: 70,000-120,000 mi

Symptoms: No-start condition, cranks but won't fire, Intermittent stalling when engine is hot, Check engine light with crank/cam sensor codes, Loss of tach signal while driving

Fix: The internal optical sensor and ignition module fail due to heat. 1999+ models switched to coil-on-plug, eliminating this. Requires distributor replacement (remanufactured units available). Timing must be reset. Labor: 1.5-2 hours.

Estimated cost: $350-600

Typical onset: 120,000-180,000 mi

Symptoms: Blue smoke on startup or acceleration, Burning 1+ quart every 800-1,200 miles, Fouled spark plugs (oil-coated), Loss of power under load

Fix: The SR20DE rings wear prematurely if oil changes were neglected or wrong viscosity used. Carbon buildup on ring lands compounds the issue. Requires engine disassembly, honing, new rings, bearings, and seals. Many opt for used low-mileage engine swap instead. Labor: 12-16 hours for in-chassis rebuild, 8-10 for swap.

Estimated cost: $1,800-3,500

Typical onset: 60,000-100,000 mi

Symptoms: Clunking over bumps from front suspension, Steering wheel off-center after hitting potholes, Uneven or cupped inner tire wear, Vague steering feel, wandering on highway

Fix: The rubber bushings crack and separate, allowing excessive control arm movement. Aftermarket bushings often fail quickly; OEM or polyurethane recommended. Requires pressing old bushings out. Alignment mandatory after. Labor: 2-3 hours both sides plus alignment.

Estimated cost: $450-750

Typical onset: 70,000-110,000 mi

Symptoms: Harsh clunk when shifting from Park to Drive, Excessive vibration at idle in gear, Transmission visibly sagging when inspected from below, Driveline shudder during acceleration

Fix: The hydraulic transmission mount fails, allowing the trans to drop and create harsh engagement. The rear mount also commonly splits. Both should be replaced together. Labor: 1.5-2 hours.

Estimated cost: $280-450

Symptoms: Fuel smell around left rear of vehicle, Fuel leaking during fill-up, Check engine light with evap codes, Difficulty inserting fuel nozzle

Fix: The steel filler neck rusts where it connects to the tank, especially in salt-belt states. NHTSA had a recall for this but coverage expired. Requires dropping exhaust and sometimes fuel tank for access. Labor: 2-3 hours.

Estimated cost: $350-600