2021 Subaru Ascent Engine Problems
- Complaints
- 12about this part
- Share
- 12%of 104 total for the year
- Median mileage
- 300miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 12 complaints about the engine of the 2021 Subaru Ascent, 12% of the 104 complaints for this model year. Where a mileage was given, the median is 300 miles. 1 a fire, according to the filers.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Unknown. I am smelling gasoline in the cabin of the car. A LOT of fumes fill my garage when I start the car. The car sometimes accelerates when I put it in park, resulting in more fumes. Fuel efficiency is lower than expected as well.”
NHTSA complaint #11442758, filed 2021-12“While driving my Subaru Ascent, a check engine warning light appeared on the dashboard. Shortly afterward, I noticed smoke coming from the engine compartment. I immediately pulled over and turned the vehicle off. Within moments, flames began coming from under the hood. The fire spread rapidly, and within 5-10 minutes the entire vehicle was fully engulfed in flames. The fire originated from the engine compartment. The vehicle was a total loss. Subaru of America was notified on 12/23/2025, but no follow-up or update on investigation has been responded. …”
NHTSA complaint #11712180, filed 2026-01“The transmission on our 2021 Subaru Ascent is slipping and failing to accelerate, RPMs reving, and every issue indicator notification light is on. We took the car to our mechanic, then to the Subaru dealership service dept for diagnosis. A full transmission replacement is required plus associated repairs for a cost of $14,543.98. Service estimate attached. This repair is more than 2/3 of the value of the vehicle. This make/model and transmission type have documented problems and Subaru has previously issued an extended warranty on other model years for this same transmission issue. …”
NHTSA complaint #11710776, filed 2026-01“Oil leaking from upper and lower oil pan. Oil seeping from head gasket and CVT chain pump cover. RTV sealant failure. $4800 to repair. Subaru needs to solve these oil leak issues. Leaking oil is bad for the environment and engine failure could cause accidents and injury.”
NHTSA complaint #11749720, filed 2026-07“Oil leak from engine constantly from FRONT DIFFERENTIAL, rec cvt pump reseal with new trans seal, pump is leaking causing drips ; drain plug is also leaking. Need to Replace Front and rear Pads & Rotors at 35k miles which is unheard of. Accessed by suberu dealership.”
NHTSA complaint #11689564, filed 2025-09Related service bulletins
- 11037946Sep 29, 2026This Bulletin provides a diagnostic procedure for customer concerns about hesitation, reduced acceleration, or lack of power when driving uphill or under heavy engine load.
- 11036821Aug 31, 2026This bulletin announces the availability of new reprograming files for the Engine Control Module (ECM) developed to remedy the following DTCs: P0016, P0017, P0018, P0019, P0014…
- 11036811Aug 20, 2026This service bulletin outlines the diagnostic and repair procedure for white smoke emitted from the exhaust after startup. This is an revised version of the original bulletin.
- 11034269Jun 30, 2026This bulletin provides updated parts information and a service procedure to follow for removing accumulated carbon deposits from fuel injectors and internal engine components…
- 11034264Jun 26, 2026This bulletin provides updated parts information and a service procedure to follow for removing accumulated carbon deposits from fuel injectors and internal engine components…
- 11034257Jun 23, 2026This bulletin outlines the diagnostic and repair procedure for white smoke emitted from the exhaust after startup.
- 11034243Jun 3, 2026This bulletin announces the design change made to the exhaust manifold flange nut material that has been changed from stainless steel to medium carbon steel. This change also…
- 11033065May 13, 2026This bulletin provides updated parts information and a service procedure to follow for removing accumulated carbon deposits from fuel injectors and internal engine components…
- 11033051May 1, 2026This bulletin announces the diagnostic procedures to be used when DTCs B1571(REFERENCE CODE INCOMPATIBILITY IMMOBILIZER CM TO ECM) and B1572(IMM CIRCUIT EXCEPT ANTENNA CIRCUIT)…
- 11027982Jan 12, 2026This Bulletin provides the diagnostic procedure for the STARLINK® Remote Engine Start (RES).
Engine: other model years
Other parts of the 2021 Subaru Ascent
20 complaintsElectrical system
18 complaintsVisibility (wipers, defrost, mirrors)
18 complaintsOther or unknown
17 complaintsLane departure
15 complaintsBrakes
9 complaintsForward collision avoidance
7 complaintsSteering
7 complaintsBody and structure
7 complaintsFuel system
2 complaintsTires
2 complaintsVehicle speed control
2 complaints
← All problems reported for the 2021 Subaru Ascent
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology