1991–2002 INFINITI G20

2.0L I4FWDAUTOMATICgas
5-Year Cost of Ownership
$50,150 maintenance + known platform issues
~$10,030/yr · 840¢/mile equivalent · $31,743 maintenance + $4,207 expected platform issues
Common Problems & Known Issues

The 1991-2002 Infiniti G20 is essentially a premium Nissan Sentra SE-R with better interior trim, sharing the SR20DE engine. It's mechanically solid when maintained, but infamous for distributor failures, transmission cooler line corrosion leading to catastrophic trans damage, and oil consumption issues on higher-mileage examples.

Transmission Cooler Line Corrosion and Fluid Cross-Contamination

Common · high severity
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

Distributor Internal Failure (Pre-1999 models)

Common · high severity
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

SR20DE Oil Consumption and Piston Ring Wear

Occasional · medium severity
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

Front Lower Control Arm Bushing Deterioration

Common · low severity
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

Automatic Transmission Mounts Collapsing

Common · low severity
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

Fuel Filler Neck Rust and Separation

Occasional · medium severity
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
Owner tips
  • Install an external transmission cooler immediately on automatic models and inspect cooler lines annually for corrosion — this single mod can save your transmission
  • Use Nissan-spec 5W-30 or 10W-30 oil and change every 3,500-4,000 miles to prevent ring wear; the SR20DE is sensitive to oil quality
  • Replace the distributor preemptively on pre-1999 models around 80k miles if no service history exists
  • Undercoat the fuel filler neck area if you live where roads are salted
  • The manual transmission is bulletproof; avoid automatics unless cooler lines have been addressed
Buy a manual transmission example with distributor already replaced and service records showing religious oil changes — avoid automatics unless you can verify cooler line replacement or plan to do it immediately.
AI-assisted summary drawn from NHTSA recall data, our labor-times database, and platform knowledge. Not a substitute for a pre-purchase inspection on a specific vehicle.
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