2019 Subaru Forester Transmission Problems

- *Incident 1 (2023):* While driving, my vehicle suddenly stopped while in drive gear, accompanied by a high-pitched alarm and multiple engine service lights. It took over 30 seconds to shift into park and restart the vehicle. The incident occurred at an intersection, and I was fortunate to avoid any collisions.

Defective/failed thermal control valve. Valve failed while I was driving, resulting in safety systems (e.g., lane keep assist, pre-collision braking). Looking this up, this is a known issue to Subaru.

Was driving in the right-hand lane on the interstate with the cruise control set, went to change lanes as I was approaching a slower moving semi truck going up an incline. Cruise control deactivated with no inputs from myself. Vehicle began to decelerate.

The Thermo Control Valve had went out. When the valve went out, the Subaru Eyesight became disabled. This also turned off the forward collision, automatic emergency braking, blind spot warning, lane departure, and rear cross traffic warning and braking.

Driving uphill when the car suddenly jolted, lost power, and all warning lights became illuminated. All safety features were disabled as well. The sudden stop almost resulted in being rear ended and the car was barely drivable afterwards.

The engines shut down or stalled on me while driving completely. It did not accelerate when I was trying to move the car off the road. the engines sputtered / shaken , all the lights came up on the dash board, smokes started to come out of my engines.

The contact owns a 2019 Subaru Forester. The contact stated that the vehicle was in the park position in a parking space but was unsure if the shifter was in park when without warning, the vehicle rolled down a hill and crashed into a chain link fence and burial wall. No warning lights illuminated.

The contact owns a 2019 Subaru Forester. The contact stated while at a complete stop at the car wash waiting for his turn, the vehicle accelerated suddenly and unintendedly, and crashed into a concrete brick wall. The air bags deployed.

The car was parked for a week while visiting. (It has recently had its 30,000 mi.service) When I got in and started it, all the dashboard lights lit up including check engine. I tried reaching a Subaru near where I was visiting.

While at a Stop as the engine turns off and awaits decompression of brake to turn on again vehicle moves forward bit, then the engine shuts down while in drive (stalls) had a vehicle hit me in rear but luckily I had my trailer hitch on because it saved me from body damage .

50k Mileage Mark: When the vehicle turned off at the stop light to save gas, the car stalled. I had to frequently put the car back in Park, and restart the engine. Since then, I had to turn off the “auto turn off” function for fear of the car stalling on the road.

The contact owns a 2019 Subaru Forester. The contact stated she turned on the vehicle, left it on, and exitto close the trunk, but after forcefully closing the trunk, the vehicle began to roll backward. The contact stated the gears were set on Park and the area was an inclined driveway.

Often, but not always, mostly when turning left from a stop as at a traffic light the car will hesitate and lose power and speed. Then I try to accelerate and the car surges forward too fast. I feel that I am going to stall in the intersection.

The electrical system fails, and the battery is not charging sufficiently. When the auto start/stop engages, the car does not restart in traffic. Requested a battery test at the dealership in May 2025; was told it could not be done that day because it would require leaving the dealer service shop.

CVT Transmission failed and not repairable. 6 months out of warranty but under mileage for warranty at 37,000 miles. Fairly new vehicle that is useless w/o $9,000 for a replacement transmission.

Subaru Transmission is wonky! Makes noise... Feels unsafe...

On April 16, 2024 the Thermo Control Valve on my 2019 Subaru Forester failed while I was going 70 mph in the middle lane of rush hour traffic. All of the warning lights came on at once as my engine stalled. I lost all mechanical power and was barely able to make it off the highway without getting hit. There was no prior warning that the Thermo Control Valve was bad. I had the car serviced at a Subaru dealership three weeks before the incident and was told that everything looked good on my car. The dealership replaced the Thermo Control Valve under extended warranty coverage. I have a second 2019 Subaru Forester that also falls in this group of vehicles, but Subaru will not replace the Thermo Control Valve until it fails.

While driving on a highway outside Milford, CT my vehicle is check engine light suddenly illuminated. I had a sudden loss of power, no heat, and the engine temperature was unable to read. Engine temperature was not accurately reporting and showed it as being cold as indicated by blue light warmup light. My eyesight, pre-collision system, and sport mode was disabled due to the engine light being illuminated. The vehicle was seen at a Subaru dealer, who diagnosed the issue to be the thermo control valve. Dealership informed me that it was unsafe to drive and I risk complete engine failure, overheating, and or fire if I continue to operate without required repair. As a result, I was stranded overnight, three hours away from home. Repair was completed on [XXX] at cost of $1830. I learned at the dealership that this is a known issue, in 2021 Subaru replace the plastic components of this part with aluminum due to similar issues experience by many customers. Customers are reporting vehicles going into “limp mode” and even engine damage. I learn that there is a class action lawsuit regarding the same issue, which can be reviewed here: [XXX] Please help to recall vehicles and push Subaru to repair/refund. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Check engine light came on and gave code P26A6 which came back the thermal control valve which is a well known issue with this make and model vehicle.

Power Control Valve malfunctioning at 26,000 miles. Causing all safety features (auto braking & lane departure) to be shut off.

When driving, ALL lights on the dash went on and vehicle safety features did not work- no cruise control, automatic breaking, automatic headlight adjustments, etc. We were over 500 miles from home and had the oil changed but it did not fix the problem. Had $72,000 miles on it, 4 years old.

My wife was driving her 2019 Subaru Forester (purchased new) and the Eyesight disabled and the check engine light came on. The car was still running, but not as it normally would. It had less power but would still maintain the speed limit.

On June 20, 2023, the "check engine" light came on my 2019 Subaru Forester and "Eyesight" flashed on my dashboard as disabled. I immediately went to my mechanic and he ran a diagnostic which showed the following: "P26A3 - Engine Coolant Bypass Valve." My car has 75,000 miles and is out of warranty for the powertrain.

On January 1, my wife was returning home from a grocery run when our 2019 Forester’s dashboard suddenly lit up like a Christmas tree--Check Engine, EyeSight, Anti-Lock Brakes, Anti-Skid, and blue Temperature lights all came on simultaneously. The Forester did not lose any appreciable power but the heater stopped working and was only blowing cold air.

Eye-sight system shutdown and the car, although it was drivable, ran rough. Since there is a huge reliance on the monitors as they are designed to "forward think" to aid the driver, this was a major disruption to the driving experience. Not knowing what the disabled components affected, was a huge cause for alarm.

Auto safety systems compromised with illumination of check engine light and engine temp warning light. Subaru dealership service department determined problem with Thermo Control Valve. Engine was not overheating as the vehicle was being driven in winter time, February in Alaska.

On 10/7/2022, all the warning lights came on and stayed on, even after tightening the fuel cap and replacing the battery. I brought the car to Ocala Subaru this morning, and paid for a diagnostic that shows the Thermal Control Valve needs replacement. Apparently this is now a common problem on this year and model Subaru.

check engine light came on end of August. Took into dealership early September (9/6/22) to find that the P26A3 code or Engine Coolant bypass Valve is defective. I have 47k miles on my 2019 Forester, so luckily it is under the powertrain warranty ( up to 60k).

The problem seems to be a faulty Thermo Control Valve Assembly. When I started the car, the dashboard lit up with several warning signs including the check engine light and 6 or 7 other warning lights. I also received texts and emails from Subaru saying to have my vehicle serviced ASAP.

The problem cited below is on a 2019 Subaru Forester with 20,101 miles. The 'check engine' light came on when I started my vehicle as well as all the ADAS warning lights came on. All ADAS were inoperable.

My 2019 Subaru Forester Sport only had 41,000 and the thermal control valve on it failed. The engine is running really cold and sometimes without warning certain safety feature shutoff as a result. There were no warning signals before it failed but when it went out the check engine light came on as well as about 5 other warnings.

The failure is affected by the braking system and control logic of the ignition key switch, gear shift and emergency break button. A coffee cup at the drive through collapsed spilling coffee. Through a sequence of moves I found myself rolling out of the drive up line, across the parking lot right towards the sidewalk and highway on the other side.

The contact's wife owns a 2019 Subaru Forester. The contact stated that as his wife attempted to park her vehicle into a parking spot, the vehicle independently accelerated while her foot was on the brake pedal without warning. The contact's wife steered the vehicle to avoid hitting other vehicles as the acceleration continued; she was eventually able to stop the vehicle.

WHEN DRIVING IN THE HIGHWAY THE VEHICLE STARTS TO JERK VERY STRONG AND HIGHWAY SPEED IS LOST MAKING IT DANGEROUS TO DRIVE AND POTENTIALLY CAUSING AN ACCIDENT. I HAVE TAKEN THE VEHICLE TO THE DEALER AND THEY WILL DO NOTHING ABOUT IT. IT IS A KNOWN ISSUE FOR THIS VEHICLE MODEL AND SUBARU IS NOT FIXING THE ISSUE. THE JERKING IS SO VIOLENT THAT IT COULD BECOME A SAFETY HAZARD FOR DRIVERS AND ANYONE ELSE ON THE ROAD. THE JERKING HAPPENS ON A DAILY BASIS AND SOMETIMES IT IS MORE STRONG.

WHEN DRIVING AT A LOW SPEED THE CAR LOST ALL POWER WITHOUT ANY WARNING LIGHTS .HAD TO PULL OVER AND LET CAR SIT FOR ABOUT 10 MINUTES THEN RESTARTED CAR. I WAS ABLE TO DRIVE BUT IT HAD VERY LOW POWER. CAR CONTINUES TO HAVE LOW POWER AND HESITATED TO ACCELERATE. CAR HAD 38,467 MILES AT THIS TIME. CAR FREQUENTLY HAS A KICKBACK FEEL WHEN ACCELERATING. WHEN PRESSING THE GAS PEDAL IT HAS A DELAY RESPONSE TO MOVE. BROUGHT IT TO THE DEALERSHIP 2 TIMES FOR THIS PROBLEM. THERE IS ALSO A NOISE COMING FROM THE RIGHT REAR AXEL OF CAR SINCE CAR WAS PURCHASED. DEALER CONTINUES TO SAY IT'S A TIRE NOISE AND THEY DO NOT SEEM TO BELIEVE THE OTHER PROBLEMS WITH THE CAR.

Tl* the contact owns a 2019 subaru forester. The contact stated that the windshield cracked and was replaced three times in a six-month period. The contact was concerned that the design of the hood and the thickness of the glass in the windshield was a contributing factor to the failures.

While driving around 30mph the car will sometimes hesitate and then lurch if the gas pedal is very lightly pressed. Sometimes it will do it at higher speeds as well, around 50mph but not typically at freeway speed. Happens on mountain roads and city streets.

Vehicle quickly developed a "surge, sputtering, jerk" type action when coasting or maintaining speeds above 35mph. Also when braking, there is good and predictable speed reduction until about 10mph when the transmissions seems to unlock and the car lunges forward since there is suddenly not enough brake pressure because the transmission has shifted for some reason.