The 2021 Impreza with the FB20 2.0L boxer is relatively young but already showing the familiar Subaru weak points: head gasket seepage, CVT cooler failures, and oil consumption issues that can escalate to catastrophic engine damage if ignored.
CVT Transmission Oil Cooler Failure
Occasional · high severityTypical onset: 40,000-80,000 mi
Symptoms: Transmission overheating warning light, Coolant mixing with CVT fluid (milky fluid on dipstick), Harsh shifting or limp mode, Coolant loss with no external leaks
Fix: Replace transmission oil cooler and flush both coolant and CVT systems completely. Critical to catch early before cross-contamination destroys the CVT. 4-6 hours labor depending on access and flush requirements.
Estimated cost: $800-1,500
Excessive Oil Consumption Leading to Engine Damage
Common · high severityTypical onset: 30,000-90,000 mi
Symptoms: Low oil warning light between changes, Burning 1+ quart per 1,000 miles, Blue smoke on cold start or acceleration, Check engine light with misfire codes, Knocking or rattling from engine
Fix: FB20 engines consume oil due to piston ring design and cylinder wall scoring. Early stage: monitor and top off religiously. Advanced cases require complete engine rebuild or short block replacement. Rebuild is 18-25 hours, short block swap 12-16 hours.
Estimated cost: $4,500-7,500
Head Gasket Seepage
Occasional · medium severityTypical onset: 60,000-100,000 mi
Symptoms: External oil weeping at head/block mating surface, Slight coolant smell or crusty residue near heads, Gradual coolant loss requiring top-offs, No overheating or white smoke (external leak only)
Fix: Classic Subaru issue, though less catastrophic on FB20 than older EJ engines. Requires pulling both heads, resurface if needed, new gaskets and timing components. 10-14 hours labor.
Estimated cost: $2,200-3,500
Transmission Mount Failure
Common · low severityTypical onset: 50,000-90,000 mi
Symptoms: Clunking when shifting from Park to Drive/Reverse, Excessive vibration at idle in gear, Visible engine/trans movement when rocking car, Harsh engagement feel
Fix: Rear transmission mount degrades and tears. Straightforward replacement, 1.5-2.5 hours. Often done alongside other mounts for preventive care.
Estimated cost: $250-450
Front Lower Control Arm Issues
Occasional · medium severityTypical onset: 60,000-100,000 mi
Symptoms: Clunking over bumps at low speed, Steering wander or pull, Uneven tire wear on inside edge, May be covered under NHTSA recall if within range
Fix: Bushings wear or arms crack at stress points. Check for active recall first (SUSPENSION:FRONT:CONTROL ARM:LOWER ARM). Replacement is 2-3 hours per side plus alignment. Often both sides done together.
Estimated cost: $600-1,200
Fuel Filter/Pump Assembly Clogging
Rare · medium severitySymptoms: Hard starting when fuel tank below 1/4, Loss of power under load or at highway speeds, Check engine light with fuel trim or pressure codes, Sputtering or stumbling during acceleration
Fix: In-tank fuel pump/filter assembly can clog from contaminated fuel or debris. Requires dropping fuel tank. 3-4 hours labor, more if tank is full or rusty hardware.
Estimated cost: $700-1,100
Buy only with full service records showing religious oil monitoring and CVT maintenance; budget $2,000-3,000 for likely FB20 oil consumption issues within 100k miles.
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.