2021 Subaru Forester Engine Problems

Your engine shuts off completely while driving, then restarts after a few seconds. This happens several times a week at random times, especially in traffic, creating a serious safety risk. When it happens, all dashboard warning lights illuminate and you see "Eyesight" with a line through it, plus a warning buzzer sounds. The problem has gotten worse since last summer. The dealer inspection didn't identify a cause, but they suggested waiting until it happens constantly. You may need diagnostics to identify electrical or sensor issues causing the engine stall and Eyesight system warnings.

Your engine suddenly lost all power while driving on the highway at 70 mph, forcing you to pull over into a dangerous shoulder area with traffic speeding past. A Texas Department of Transportation vehicle had to push your car about half a mile to safety. The dealer found that your Thermo Control Valve had failed, which they said is a common problem on this model. Subaru covered the repair under an extended warranty for this part, but you believe they should have replaced it proactively instead of waiting for it to fail.

Your 2021 Subaru Forester has stalled multiple times without warning lights appearing — first at a traffic light, then repeatedly while driving. The dealer replaced the battery and fuel injectors, but the stalling continued even after repairs, including an incident where the engine jerked abnormally before stalling. A dealer diagnostic couldn't identify the root cause. The fix may involve further electrical system diagnosis, fuel system testing, or engine control module evaluation to find why the engine is shutting off unexpectedly.

Your car surges (jerks forward) during acceleration. The dealer found carbon buildup on the engine intake valves, which is causing poor fuel economy, higher emissions, and performance problems. The valves need professional cleaning to fix the issue, which costs around $300 and isn't mentioned in your scheduled maintenance guide. A professional fuel system or intake valve cleaning service will be required to remove the carbon deposits.

Your engine unexpectedly shuts down while your car is parked at traffic lights or stop signs, accompanied by a beeping sound. The dashboard may display an "Eyesight disabled" message, though this appears unrelated to the shutdown. This problem occurs intermittently and can't be reliably reproduced. The fix will likely involve diagnosing the engine control system and potentially updating or replacing components related to idle control or engine management.

2021 Subaru forester limited- Stop Start when stopping at a red light. Sometimes the engine does not restart when releasing the brake pedal. Message on dash put car in park and press start. Occurred. April 24 2025 and May 5 2025

Was stopped at traffic light. Start Stop system was engaged. Engine turned off as normal. When I took my foot off the brake the engine did not engage and the Eyesight warning light came on that the Eyesight system was not functioning. Put the car in park and engaged the ignition button and the engine started. Turned off the Start Stop system and the car functioned normally after that. Have read postings on Subaru forum that this has happened to others.

Thermo control valve defective. Not informed one week ago when I purchased car at end of lease. Problem known to Subaru since 2019 or sooner. Would not have purchased if I had been notified about this major problem

Vehicle was parked and idling unoccupied for under 5 minutes when an extremely noxious, hot blast of fumes came from underneath the back. Black smoke immediately entered the passenger cabin through the vents and flames were visible in the engine compartment and running onto the ground. Entire vehicle was burned beyond recognition in a matter of minutes. Ten days earlier the TCV, a known problem, had been replaced at a dealership per TSB 09-80-21. The vehicle had been driven under 300 miles since the replacement. Afterwards, a manufacturer rep inspected the vehicle, indicated the fire started in right rear of the engine compartment, could have possibly been a fuel leak, but damage was too extensive to determine the exact cause. The referenced TSB explicitly requires a new fuel line for every TCV replacement.

The contact owns a 2021 Subaru Forester. The contact stated while driving 10 MPH, the vehicle became inoperable. The vehicle stopped independently and failed to respond to the brake or accelerator pedal being depressed. The vehicle was turned off and restarted and returned to normal functionality. The contact stated that the Eyesight detection warning light was illuminated. The vehicle was diagnosed but the cause of the failure was not determined. The vehicle had not been repaired. The manufacturer was made aware of the failure and advised the contact to bring the vehicle in for an extended time. The failure mileage was approximately 34,000.

My vehicle stalls at stop signs and red lights at Least once or twice a day regularly I’ve taken to the dealer and they said I was the reason it does that but the car is barely 2 years old bought new it has been doing that since last year it needs to be fixed

Engine stalled 2x within 8 days at major intersections (both times), therefore blocking a lane in the intersections. Was told 1st time it was a gliche by dealership. Upon researching prior recalls for this make and model, engine stalls have been an issue. Dealership still can’t figure out issue.

The contact owned a 2021 Subaru Forester Sport. The contact stated while driving at 75 MPH, the front end of the vehicle crashed into a small deer. The air bags did not deploy. The contact veered to the side of the road. The contact's friend who was occupying the front passenger seat exited the vehicle and inspected the front end of the vehicle. The contact's friend then advised her to immediately exit the vehicle as there were flames underneath the hood of the vehicle. The contact stated while she was exiting the vehicle and letting her three dogs who were occupying the rear seats out of the vehicle, the fire expanded to the entire front end of the vehicle. The contact stated that the vehicle burned significantly. The contact was able to extinguish the fire with the assistance of the fire department. A fire department report was filed. A police report was filed. The vehicle was towed to an independent mechanic, where it was totaled. The contact sustained a soreness on the right knee but did not seek medical assistance. The dealer was notified of the failure but did not provide any assistance. The manufacturer was not notified of the failure. The failure mileage was approximately 20,000. The VIN was unavailable.

This is in reference to tracking # 11462054, a third incident of sudden engine power loss/deceleration. On 04/27/2022 the 2021 Subaru Premium was returned to the selling Subaru dealer to try and fix the two previously reported problems . They found no codes in memory and no problems when road tested. I left the dealer to return home, and about 10 min. after, on a two lane city street, the engine suddenly lost power while I was going about 25mph, and decelerated to about 10mph before regaining power. I drove back to the dealer and a service rep came with me for a road test of several miles, where the car operated normally. At the dealer, there was no code in memory. The mileage was about 13,135. No paperwork was provided by the dealer. How to resolve this problem???

On 04/02/2022, several minutes after having filled the gas tank, I was driving at about 35 mph on a two lane road at constant throttle, when the engine suddenly lost power for several seconds before it regained acceleration. There was a pickup truck following me very closely and it swerved around me to avoid hitting me. On 04/13/2022 , several minutes after leaving my driveway, at about 27 mph on a two lane road, the engine again lost power for several seconds before resuming power. In the first case the engine was at operating temp., in the second case it was cold. I will take the vehicle to the Subaru dealer from whom I purchased it in a couple of days to evaluate the problem, which I consider to be serious. In both cases I was so surprised that I didn't look at the tach etc. 12,500 miles.