2018 MITSUBISHI MIRAGE G4

Typical onset: 60,000-100,000 mi

Symptoms: metallic knocking or rattling at startup or idle, low oil pressure warning light, excessive oil consumption between changes, check engine light with knock sensor codes

Fix: The 1.2L 3-cylinder develops main and rod bearing wear prematurely, especially in vehicles driven hard or with extended oil change intervals. Common fix requires crankshaft polishing or replacement, new bearings, possibly pistons and rings if cylinder scoring is present. Engine-out job: 18-24 hours labor for short block work, full rebuild 24-32 hours.

Estimated cost: $3,500-6,500

Typical onset: 50,000-90,000 mi

Symptoms: transmission fluid leaking from front of vehicle near radiator, transmission overheating warning, erratic shifting or loss of drive, milky transmission fluid indicating coolant contamination

Fix: The external CVT oil cooler develops internal leaks allowing coolant and transmission fluid to cross-contaminate. If caught early (external leak only), cooler replacement is 2-3 hours. If coolant entered the CVT, full transmission flush or replacement required: 8-12 hours for CVT R&R. Always replace cooler AND flush cooling system.

Estimated cost: $800-1,200 (cooler only) or $3,000-4,500 (with CVT damage)

Typical onset: 40,000-80,000 mi

Symptoms: clunking when shifting from park to drive or reverse, excessive vibration at idle, visible engine/transmission movement when accelerating, hesitation or jerk during throttle tip-in

Fix: The rear transmission mount rubber deteriorates quickly on this platform. Replacement is straightforward but requires supporting the powertrain. 1.5-2 hours labor. OEM mount recommended as aftermarket versions fail even faster.

Estimated cost: $250-400

Symptoms: rough idle or stalling, hesitation under acceleration, difficulty starting when hot, check engine light with lean fuel codes

Fix: Vehicles running on lower-quality fuel or imported to regions with different fuel standards can develop in-tank fuel filter restrictions. The filter is integrated into the fuel pump assembly. Requires tank drop: 2-3 hours labor. More common in vehicles imported from overseas markets.

Estimated cost: $400-650

Typical onset: 70,000-110,000 mi

Symptoms: coolant smell from engine bay, white residue around head/block mating surface, slight coolant loss with no visible external leaks, overheating in severe cases

Fix: The 1.2L develops external head gasket weeps more often than internal failures. If caught early and no overheating occurred, head gasket replacement is 8-10 hours labor. Always check head for warpage and resurface if needed (add 2-3 hours). Internal coolant contamination into cylinders is rare but catastrophic.

Estimated cost: $1,200-1,800

Symptoms: airbag warning light illuminated, potential airbag non-deployment in crash

Fix: NHTSA recall for airbag system defects. Check VIN for open recalls before purchase — unrepaired recall vehicles may have non-functional safety systems. Dealer repair is free but requires appointment. 1-2 hours dealer time.

Estimated cost: $0 (recall repair)