Table 1 shows one common other fuel system related problems of the 2021 Subaru Ascent.
| Problem Category | Number of Problems |
|---|---|
| Other Fuel System problems |
On may 14, 2026, while driving a 2021 Subaru Ascent (approx. 94,291 miles) on a texas expressway at highway speed during rush hour, I experienced a sudden and significant loss of engine power. There were no warning lights, no safety system activation, and no advance indication of the failure. The vehicle decelerated abruptly with traffic behind it. Live obd-ii data was being logged during the drive and was provided to the service advisor at the authorized Subaru retailer. This incident occurred only 3 days and approximately 125 miles after the vehicle was returned following a major engine repair performed at an authorized Subaru retailer in texas under active powertrain warranty. That repair was supervised by a Subaru of America district quality manager and field technical specialist, who conducted a 110-mile validation drive prior to release. Prior to the highway failure, visible fluid leaks were documented across the intake ducting, residue on lower engine components, a sweet and burning odor after driving, and milky sludge returning to the coolant reservoir — all within 125 miles of pickup. These are consistent with ongoing oil and coolant cross-contamination, which was the original diagnosis documented in the dealership's digital service portal. The vehicle has now undergone three major engine teardowns since March 17, 2026 — over 100 days out of service — for the same underlying powertrain issue on the fa24 engine. The current repair involves cylinder heads sent to a third-party machine shop. Vehicle telematics confirm the vehicle has not been started since may 27, 2026. This report is filed to establish a federal safety record of the highway power loss incident and the recurring nature of this powertrain failure. An active Subaru of America customer advocacy case is on file regarding this vehicle.
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.