This Bulletin provides the diagnostic procedure for the STARLINK® Remote Engine Start (RES).
full bulletin at NHTSA ↗2015 Subaru Legacy engine problems
severe 13 complaints filed with NHTSA · avg repair $3,100 · see engine across all vehicles →
Failure mileage
Complaints
13
Recalls
0
Avg fix
$3,100
2crashes
1fire
4injuries
When does it fail?
Of the 13 engine complaints filed for the 2015 Subaru Legacy, here's the actual mileage breakdown — failures cluster heaviest at 75,000-100,000 mi.
0-25k
25-50k
50-75k
75-100k
100-125k
125-150k
150k+
Each bar shows the share of total complaints filed at that mileage range. Peak failure window highlighted. Some owners report problems earlier; some make it well past 150,000 miles symptom-free. Maintenance habits and driving conditions shift the curve as much as mileage alone.
What stands out
No new NHTSA engine complaint has been filed on this vehicle in over 6 years — the issue may be aging out of the active population.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
This bulletin announces the diagnostic procedures to be used when DTCs P2096 (POST CATALYST FUEL TRIM SYSTEM TOO LEAN BANK 1) and P2097 (POST CATALYST FUEL TRIM SYSTEM TOO RICH BANK 1) are detected by the Engine Control Module (ECM).
full bulletin at NHTSA ↗This Service Information Bulletin provides the Service Manual Correction to the diagnostic procedure for DTC B2A16 (Immobilizer Key Collation Diagnosis).
full bulletin at NHTSA ↗This bulletin announces the diagnostic procedures to be used when DTCs P2096 (POST CATALYST FUEL TRIM SYSTEM TOO LEAN BANK 1) and P2097 (POST CATALYST FUEL TRIM SYSTEM TOO RICH BANK 1) are detected by the Engine Control Module (ECM).
full bulletin at NHTSA ↗In the interest of customer satisfaction Subaru of America, Inc. (SOA) is extending the New Car Limited Warranty coverage in the models listed. The extension will address instances of “phantom braking” or the EyeSight/RAB systems causing unnecessary stoppage/slowing of the vehicle.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The 2015 Legacy engine cluster shows two dominant failure patterns. First, internal sealing and oil control: multiple owners report low oil warnings and excessive consumption (one quart between services, another burning a quart every 3,000 miles). One owner's dealer confirmed short block replacement needed at $6,500; that owner states the service department called it common, pointing to factory liquid sealant degradation. Second, drivability and power delivery: owners report sudden surging with heavy shaking while idling, hesitation and delayed throttle response during low-speed maneuvers (happening as early as 300 miles), complete unintended deceleration grinding the vehicle to a halt on a highway (resulting in a high-speed rear-end collision), and engine stalling during city and freeway driving. One owner reported water leaking into the engine bay during winter with a burning smell; the dealer found nothing wrong.
Additional issues include a fractured front exhaust pipe at 140,000 miles that had already been replaced under campaign WUJ-95, strong exhaust smell invading the cabin at idle, and warning lights that the owner suspects were inadequately addressed by recall repairs (Campaigns 15V502000 and 15V366000). Cost for short block alone is substantial; other repairs and diagnostics vary. Owners express frustration that dealers acknowledge some issues as known problems but dispute manufacturer responsibility.
Same Subaru Legacy engine reports on nearby years: 2012 · 2013
Failure modes owners describe
Short block failure with oil seepage
Engine internal sealing failure leading to oil loss. Owners report low oil warning lights and complete short block replacement needed. One owner cites factory liquid engine sealant degradation as root cause.
When: Under 75,000 miles reported in one case; another case at 155,000 miles with excessive oil consumption.
Symptoms owners cite: Low oil warning light illuminating; Oil level dropping approximately one quart between services; Excessive oil consumption every 3,000 miles
Repairs/costs cited: Short block replacement quoted at $6,500. Oil changes performed by independent mechanic noted.
Recalls/TSBs owners mention: Subaru service department reportedly acknowledged this as a known manufacturing issue with newer Subaru engines due to factory liquid engine sealant degradation.
Engine surge and rough idle
Uncontrolled engine surging with heavy shaking and thunderous roar while vehicle at rest or in traffic, creating acceleration hazard.
When: At low mileage (vehicle relatively new at time of complaint)
Symptoms owners cite: Sudden engine surge with thunderous roar; Heavy shaking and vibration; Rough idle in traffic; Prior weeks of shuddering during braking
Repairs/costs cited: Not yet diagnosed or repaired at time of complaint.
Hesitation and delayed throttle response
Engine hesitates on acceleration, particularly during low-speed maneuvers or after highway driving. Multiple occurrences within first 900 miles.
When: 300 miles and 900 miles on vehicle odometer
Symptoms owners cite: Hesitation on acceleration with no initial response; Delayed acceleration after hesitation; Multiple hesitations (5-7 big hesitations) over short time period
Repairs/costs cited: Returned to dealer for repair; no repair details provided.
Sudden unintended deceleration on highway
Complete loss of engine power while driving on highway at operational speed, grinding to halt without driver input and creating stationary hazard resulting in rear-end collision.
When: Mileage not specified
Symptoms owners cite: Sudden complete deceleration without driver input; Engine grinding to halt in traffic lane; Total loss of vehicle mobility
Repairs/costs cited: Not provided; resulted in collision.
Engine stalling during operation
Engine stalls while vehicle in motion on city streets and highways. One case attributed to O2 sensor failure; another involves battery terminal issues.
When: Mileage not specified
Symptoms owners cite: Engine stall while driving; Check engine light illumination; Multiple stall events in different driving conditions
Repairs/costs cited: One case: O2 sensor replacement by dealer. Another case: Negative battery terminal with sensor and positive terminal replaced by independent mechanic.
Water ingress into engine bay with burning smell
Water leaks into engine compartment during winter driving, creating burning odor. Issue recurs despite dealer inspection.
When: 4,400 miles
Symptoms owners cite: Water leaking into engine; Burning smell from engine bay; Recurrent failure after initial inspection
Repairs/costs cited: Dealer inspection performed; technician stated vehicle operating to specification. No repair completed.
Exhaust smell in cabin
Strong exhaust fumes entering cabin while vehicle at idle, worsening over time. No external leaks detected.
When: Mileage not specified
Symptoms owners cite: Strong exhaust odor in cabin during idle; Odor intensifying over time; Daily occurrence
Repairs/costs cited: No leaks detected.
Fractured front exhaust pipe
Front exhaust pipe fracture requiring replacement. Same component failed previously under manufacturer campaign.
When: 140,000 miles
Symptoms owners cite: Fractured front exhaust pipe
Repairs/costs cited: Front exhaust pipe replacement required; previously replaced under Subaru Campaign WUJ-95 for same failure.
Recalls/TSBs owners mention: Campaign WUJ-95 issued for front exhaust pipe; however, failure persisted after repair.
Warning light issues and recall remedy sufficiency
Multiple warning lights flashing on instrument panel. Dealer performed recall repair (Campaign 15V502000 and 15V366000) but remedy may have been insufficient, contributing to subsequent crash and fire.
When: 25,100 miles
Symptoms owners cite: Multiple warning lights randomly flashing; Vehicle fire after crash following recall repair
Repairs/costs cited: Recall repairs performed per Campaigns 15V502000 (Powertrain) and 15V366000 (Exterior Lighting, Forward Collision Avoidance); remedy sufficiency questioned.
Recalls/TSBs owners mention: Manufacturer recalls 15V502000 and 15V366000 applied, though owner questions effectiveness.
Synthesized from 13 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 2 most recent
Strong exhaust fume smell invades cabin while idle, everyday and it's getting stronger no leaks detected
Short Block needs to be replaced ($6,500) Yes, Scenic Subaru has the vehicle awaiting status of repairs (who is paying for service) Yes, my safety is at risk as the oil light has come on during the night when I'm alone on a deserted road. Service Department knows what the problem is - they are seeing alot fot this problem. Unknown on Inspections Yes, warning 'low oil' light came on. The oil…
Had engine trouble with your 2015 Subaru Legacy?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2015 Subaru Legacy?
It's a meaningful issue. 13 complaints have been filed and the failure mode causes operational problems for owners. Repairs average $3,100.
At what mileage does the engine typically fail?
Across the 8 complaints that reported odometer mileage, most engine failures cluster between 17,400 and 140,000 miles, with the median around 41,300. A quarter of owners report trouble before 17,400; a quarter make it past 140,000. Maintenance history matters more than the odometer alone — this is the reported failure window, not a guarantee.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2015/Subaru/Legacy.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.