2021 Subaru Forester: sudden loss of power

Filed Oct 3, 2026 · Engine, Fuel system · CA

On two separate occasions, less than one year apart after Subaru Service replaced my battery with a “larger” battery without my knowledge my vehicle suffered sudden, catastrophic electrical failure while moving in active highway traffic, causing an immediate loss of propulsion and creating a life-threatening safety hazard. This has happened two times the second time less than a year after the “larger” battery replacement. This car has less than 50,000 miles on it and has a perfect service record all done at AutoNation Subaru Carlsbad. We refuse to drive this car, even though it has been serviced and a new battery has, yet again, been installed. We have no faith in this car and are not willing to put ourselves in a life-threatening situation again. We also do not feel comfortable selling this car, even though we have received many above market offers. We do not feel that we can sell this car in good conscience to an unknowing next victim. It is unsafe to drive and can lose power at any moment while driving without any explanation given from Subaru. The first battery failure occurred prematurely in August 2025. Asked repeatedly why a car battery would fail while driving? Could not get a straight answer except that someone finally said it could possibly be from the auto stop start system The new larger battery failed less than one year later in August 2026, so it didn’t even last a year and it was larger. The service department at AutoNation Carlsbad told me my car passed all the test and I have nothing to worry about. This goes against any common sense. How could this happen 2 times where no issue has been disclosed. Both situations were extremely traumatic and dangerous and I feel lucky that I was able to come out of it. I’m not sure the next time would be the same. We are not able to drive this car because common sense tells us there is a bigger issue going on. So far we’ve communicated with Subaru of America and were denied California Lemon law without reason.

Filed Jun 13, 2026 · Electrical · MI

Driving along and various system warnings came on, then started losing power, then the engine died and the car was completely dead. Got a jump start and the car ran for a couple of minutes and died again. Had it towed to a repair shop and when they checked it the next morning, they couldn't find a problem and it ran great for them. I replaced the battery and alternator just to be safe because we were about to leave on a trip.

Filed Jan 26, 2026 · Engine · TX

On January16,2026 while driving from Houston,TX to Austin TX the vehicle experienced a complete loss of power on Highway 71 W. We were traveling at approximately 70 MPH when the engine completely failed. We were forced to immediately pull over onto a narrow shoulder Our situation at that point was dire: we could not exit the vehicle as other cars were speeding by. Fortunately an emergency vehicle from the Texas Department of Transportation pulled up behind us with his emergency lights flashing. He told us we were in a dangerous situation and, due to our location, he was not able to tow us to safety. Our only option at that point was to allow the emergency vehicle to puss us to a safe location off of the highway. The driver pushed our vehicle approximately 1/2 mile to a motel parking lot. We contacted Austin Subaru, arranged for a tow truck, and proceeded to the dealer. The dealer technician advised us the Thermo Control Valve had failed. We were told this failure was common. The repair was at no charge since Subaru, being aware of the problem, had extended the warranty on this part. The action by Subaru to extend the warranty instead of proactively replacing the part before failure seems blatantly irresponsible

Filed Feb 9, 2024 · Electrical, Steering · IL

The automatic shut off feature causes the car to lose all power. No power at all in the middle of traffic and I can't even use hazard lights to warn anyone. When at a stop the auto shut off turns off the car and when I take my foot off the brake it completely dies. It has happened 5 times in the last 3 days. Very dangerous. Imagine this happening on the freeway during rush hour. It's a miracle if no one has been killed. I saw countless posts from others on different forums. I have only owned this car for a week and half, taking it to the dealer today. This needs to be a recall paid for by Subaru, it is unacceptable.

Filed May 5, 2022 · Engine · VT

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???

Filed Apr 25, 2022 · Engine, Transmission · 12,500 miles · VT

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.