The 2015 Impreza with the FB20 2.0L naturally aspirated boxer is generally more reliable than its turbocharged siblings, but suffers from characteristic Subaru head gasket seepage, CVT cooler line failures, and occasional piston ring issues that lead to excessive oil consumption.
CVT Transmission Oil Cooler Line Failure
Common · high severityTypical onset: 60,000-120,000 mi
Symptoms: Transmission fluid puddle under car, often pink/red, Overheating transmission warning light, Burning smell or erratic shifting before total failure
Fix: Replace both CVT cooler lines (they're rubber-lined steel and corrode from inside out). Takes 2-3 hours including fluid refill and proper CVT flush. Critical to catch early before transmission overheats and damages internal clutch packs.
Estimated cost: $400-800
Head Gasket Seepage (External)
Occasional · medium severityTypical onset: 80,000-150,000 mi
Symptoms: Oil weeping from cylinder head seam, visible on block, Slight coolant smell or crusty residue near head/block junction, NOT the catastrophic internal failure of older EJ engines, mostly a seepage issue
Fix: Unlike EJ25s, the FB20 rarely blows head gaskets internally, but external seepage is common. Requires engine removal or substantial disassembly. Plan 12-16 hours labor. Many owners live with minor seepage if not severe.
Estimated cost: $2,000-3,500
Excessive Oil Consumption / Piston Ring Wear
Occasional · high severityTypical onset: 50,000-100,000 mi
Symptoms: Burning 1+ quart of oil every 1,000-1,500 miles, Blue smoke on startup or hard acceleration, Low oil warning light between changes despite proper maintenance
Fix: Subaru had extended warranties on some VINs for this. Requires short block replacement or full engine rebuild with new rings and honing. 18-24 hours labor. This is the big-ticket nightmare on otherwise reliable FB20s.
Estimated cost: $4,500-7,000
Transmission Mount Failure
Common · low severityTypical onset: 70,000-120,000 mi
Symptoms: Clunking when shifting from park to drive or reverse, Excessive vibration at idle, smooths out at speed, Visible sag or torn rubber on rear transmission mount
Fix: Rubber deteriorates and tears. Rear mount is most common failure point. Simple replacement, 1-1.5 hours. Do all mounts if one fails, they age together.
Estimated cost: $250-500
Brake Light Switch Failure (Recall Item)
Occasional · medium severitySymptoms: Brake lights stay on constantly or don't illuminate, Cruise control won't engage, Push-button start won't work (thinks brake not pressed)
Fix: Covered under NHTSA recall. Switch above brake pedal fails. Takes 0.5 hours if paying out of pocket post-recall. Check if recall was completed on any used example.
Estimated cost: $150-250
EyeSight Pre-Collision System False Alerts
Occasional · low severitySymptoms: EyeSight disabled warning on dash, especially in rain/snow, False emergency braking activation, Camera error messages requiring restart
Fix: Often caused by windshield replacement with wrong glass or camera misalignment. Requires dealer-level recalibration (2 hours) or camera replacement if hardware failed. Some cases are software updates only.
Estimated cost: $300-1,200
Solid daily driver if oil consumption and CVT cooler lines are verified healthy — avoid high-mileage examples without documented CVT maintenance or showing excessive oil use between changes.
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.