10.0

really awful
Crashes / Fires:
1 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
382 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2020 Subaru Forester drivetrain problems

drivetrain problem

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2020 Subaru Forester Owner Comments (Page 1 of 2)

problem #21

Jan 122024

Forester

  • miles

A D V E R T I S E M E N T S

Got warning P2A63 that the Thermo Control Valve is shot around 63k miles. Apparently this is happening very often in Subaru's made between 2019 and 2022.

- Glendale, CA, USA

problem #20

Jun 112023

Forester

  • miles
While accelerating to merge in the freeway the Thermo Control Valve malfunctioned, causing check engine light to come on which turned off all the safety features (lane assist off, precollision off, RAB and eyesight off) of my Subaru 2020 Forester Sport. I-??ve researched the internet and shows it is a common issue. I brought it to a subaru dealership and was told it is not safe to drive the vehicle. Since I just passed 60k powertrain warranty (around 62k), it is not covered and had to pay over $3,000.

- Pleasant Hill, CA, USA

problem #19

Dec 152023

Forester

  • miles
The thermo control valve (TCV) went bad at 54,000 miles. The result is that none of the safety features work anymore. Collision detection, Eye-Sight, lane change warnings, anti-skid, etc. all go offline when the TCV goes out. We can drive the car but it now has no safety features.

- Kaysville, UT, USA

problem #18

Nov 292023

Forester

  • miles

A D V E R T I S E M E N T S

The Thermo Control Valve failed at 33,945 miles. Because of this, the heater, Eye Sight, Cruise Control, Lane Assist, and Collision Brake did not work. The engine was then only running at "Sport" mode. It did not regulate the heat to the oil and could've caused sludge. The problem was confirmed by a Subaru Dealer Service Shop. I only noticed this problem when the blue thermometer light came on the dash board. Usually I wait about 5 min and once the car is warmed up the light goes away. This time the blue thermometer warning light did not turn off and stayed on for the remainder of the trip. When the car was restarted on the same day the engine check light came on. Eye Sight, Lane assist and Collision assist lights were on.

- Mclean, VA, USA

problem #17

Nov 022023

Forester

  • miles
41k miles P26A3 P26A5 ****Eyesight disabled*** ***Forward collision disabled *** Failed TCV and dealer will not cover because warranty period is over.

- Norco, CA, USA

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problem #16

Sep 302023

Forester

  • miles
Engine check light came on and after running a test it seemed as though the thermo control valve thermostat was not working properly which means the valve that lets coolant into the engine doesn't know what the temp is and when to release coolant. That ended up being the issue and we were barely under the 60k mile warranty for the powertrain so it was covered but I've been reading that it is a common issue and others are surprised it hadn't been recalled yet as it could cause the engine to overheat. The part is so defective that subaru has already designed a better part which means they know its a common issue.

- Oregon City, OR, USA

problem #15

Aug 192023

Forester

  • miles

A D V E R T I S E M E N T S

The thermo control valve malfunctioned causing the check engine light to come on which shut down all the safety features in the vehicle including the front eye sight camera, blind spot warning, the rear automatic braking, lane departure warning, adaptive cruise control, and lane keeping assistance. The check engine computer readout diagnostic trouble code was P26A5 "Engine Coolant Bypass Valve "A" Position Sensor Circuit Range/Performance". The vehicle was taken to a Subaru dealer who found the thermo valve performance was out of spec. The valve was replaced. This vehicle has not been recalled although the manufacturer replaced the part in 2021 vehicles acknowledging the valve was faulty. Because of the mileage on my vehicle, it was not covered under the warranty although many have been replaced under the manufacturer's warranty due to the failure of this valve under the 60,000 mile warranty. Through a "Goodwill gesture" Subaru replaced the part in my car at no cost. I believe this should be a recall item for others who experience this issue.

- St. Charles, MO, USA

problem #14

Jul 282023

Forester

  • miles
While driving, the 202 Forester, the check engine light, collision light, eyesight function lights all went on at the same time. I brought vehicle to check diagnostics and it is showing Engine Coolant Bypass Valve "A"Control Circuit low in Power Train System. Their were no messages prior to all the lights turning on and I was able to bring into the dealer for oil change but not able to make an appointment for repair for a few days from now

- Danbury, CT, USA

problem #13

Jul 062023

Forester

  • miles
I was driving on a paved two lane rural route and hit a small bump in the road. Immediately, my check engine light came on and all the safety features turned off. Control panel showed multiple safety features off and the Sport mode indicator light blinking. My car only has 17K miles on it and I have had it just over a month. I was able to drive it safely home and when I called the dealership the next morning I was told I could continue to drive it until the service appointment six days later. When I got home, my husband checked it with his CEL reader and got the code for the temperature control valve (an issue known by Subaru). This was confirmed by the dealership and I was told after having driven it for several days that it should not be driven. The repair is being covered under the power train warranty.

- Appomattox, VA, USA

problem #12

Jul 032023

Forester

  • miles
Our thermo control valve (TCV) assembly failed and caused dangerous loss of speed and control while on the highway. Subaru is fully aware of the defect in their design as they issued a service bulletin to inform their service centers of a new, fixed TCV assembly that is retaining the same part number (a notice only sent to their service centers, NOT to owners). Please see attached. Despite being aware of the defect, Subaru has not voluntarily replaced the defective TCV assemblies or even bothered to notify owners. Instead, they are letting us put our families and other drivers in dangerous situations through sudden loss of control. There are pages and pages of other owners experiencing this dangerous issue and - like me - being surprised to find it's a known issue that Subaru is not proactively fixing (see any of the owner forums like subaruforester.org).

- Boise, ID, USA

problem #11

May 242023

Forester

  • miles

A D V E R T I S E M E N T S

The thermo-valve controller gives out on this vehicle. Through searches and discussions with two separate dealerships, this seems to be an incredibly common issue. It's enough that Subaru has actually completely replaced the design of this piece for whenever it gets replaced. This triggers a check engine light which already removes many features on the Subaru. My understanding is that this part controls and measures the engine temperature which means that drivers have no clue if their engine is overheating or not when it goes out. Subaru has gotten away with covering this part over their Powertrain warranty since the vast majority of their vehicles are having this part break within 3 years. Most drivers are happy with this because the major ($1500-2000) repair is covered. The issue is that people that drive more often, like myself, are stuck footing the bill for a part that Subaru has admitted doesn't work properly just because we've now fallen out of this 60k mileage warranty. From my research, it's not a part that is greatly affected by mileage, so much as time since the dealerships have noted that every replacement they've seen has fallen within 3 years, regardless of the mileage. For that, I'm asking that there be a true recall put in place for this part. This is a major expense for almost anyone and isn't fair for Subaru to hide behind a warranty that won't apply to everyone when they know they created this improperly. Even the reps at the dealership mentioned that they see this far too often for it not to be a recall, but that most people are still under 60k miles, so there aren't normally issues.

- Georgetown, TX, USA

problem #10

Apr 132023

Forester

  • miles
While driving the vehicle suddenly stalled and stopped running. The dashboard illuminated with most lights and the check engine message came on the screen. I was thankfully able to get into the shoulder on the road safely without creating an accident or getting injured. The vehicle would not start again and had to be towed to the dealership. I am now out $1800 because I am slightly over my powertrain warranty in mileage on the vehicle. This is a known issue in bulletin: https://static.nhtsa.gov/odi/tsbs/2022/MC-10208664-0001.pdf I am not only disappointed with Subaru of America and NHTSA that this is not already a recall but I am also willing to seek legal action and compensation if this repair is not going to be covered. There are many incidents and reports online of similar issues: https://www.subaruforester.org/threads/2019-thermo-control-valve-assembly-and-warranty-merged-thread.823510/ https://www.carcomplaints.com/Subaru/Forester/2020/drivetrain/power_train.shtml I have filed a case with Subaru of America corporate and am waiting to hear back. Someone is going to cause an accident or end up dead because of this faulty part. It is borderline criminal that this is not already a recall.

- Palmyra, PA, USA

problem #9

Dec 282022

Forester

  • miles
Thermo control valve stays open. Needs replacement. Automatic brakes have gone on with no car in front of vehicle. Unsafe.

- San Jose, CA, USA

problem #8

Oct 202022

Forester 4-cyl

  • miles
The other day, the check engine light came on & Eyesight was disabled. I take it to the nearest mechanic who tells me that the cooling fans are running too long at idle & this could drain the battery. He also tells me to watch for the engine overheating. The recently checked coolant level had dropped lower than the minimum. I take it to dealer who keeps it for day. Similar to the 2 other complaints, the fault is related to TSB-09-80-21R calling for replacement parts to be installed. Subaru did not do any recall but instead waited for the parts to fail. I have minimal heat & the engine runs cool a lot of the time which affects emissions. My gas mileage is getting worse. The part is on backorder with no estimated time of arrival. I was told to just keep driving it & to let them know if it starts to run rough. The dealer said there are a lot of other cars & drivers in this situation at the dealer-€™s service department.

- Oakland, CA, USA

problem #7

Aug 022022

Forester

  • miles
Subaru has a known issue with a Thermo Control Valve in Foresters. Apparently the part is failing all over the place and they redesigned the part and are replacing it. The problem is the part is backordered and the dealerships are telling people it is safe to drive the car. Our car completely shut off at highway speed. I have since learned this is happening to a number of other owners who were also told it was safe to drive it while the part is back ordered. This vehicle has a lot of advanced driver features and some or all of them are shut off when this happens. Very dangerous for them to tell people to keep driving it and the vehicle should be recalled to replace the defective part that is failing.

- Virginia Beach, VA, USA

problem #6

Feb 172022

Forester

  • miles
At the time, time, car was not fully 2 years old.. its brand new.This is an addition to a post created a week ago. After the dealership offered to detail the interior of the car to solve the sulferic acid feeling I noticed that the flap above the driving wheel started to feel warm. This happened right in the morning in February. I'm not sure if I am feeling an electrical voltage, smelling the exhaust or there's still sulferic acid in the car. Every once in awhile I my hair smells like oil.. Whatever it is it makes your head feel heavy. My toddler feels something because during a drive he will say " hot". This puts our safety at risk if we are smelling the exhaust or feeling voltage while driving in the car. Sometimes it smells like fuel I the trunk of the car or acidic

- Rocklin, CA, USA

problem #5

Dec 162021

Forester

  • miles
Ever since we purchased our Subaru, the RPM's seemed a little off and then at random times when I put it in reverse, it will just idle and I will slowly press on the accelerator and it will not engage in reverse and then random pop into gear and lunge backwards. It doesn't happen every time, but is scary when it does. This has been happening pretty much since we purchased

- Friday Harbor, WA, USA

problem #4

Aug 182021

Forester

  • miles
When climbing shallow hills, car will buck and surge. Engine RPM seemed to stay constant. The transmission seemed to be unable to decide on which gear it should be in. No accident occurred, but surging made the car's performance unpredictable in traffic. Reported to dealer, who noted that this has happened to other cars in the past.

- Annapolis, MD, USA

problem #3

Feb 232021

Forester

  • 7,500 miles
Vehicle was stationary. Foot on brake in parking spot. Then vehicle accelerated on its own.

- Bronx, NY, USA

problem #2

Jul 282020

Forester

  • 500 miles
The contact owns a 2020 Subaru Forester. The contact stated that while driving and approaching a stop, the vehicle independently accelerated and vibrated for approximately 3 seconds before returning to normal operation. There was no warning light illuminated. The failure recurred several times. The contact called fox marquette Subaru located at 3825 us 41 West, marquette, mi 49855, where it was stated that the vehicle performed as designed. The contact was informed to bring the vehicle back in ten days if the failure persisted. The manufacturer was not notified of the failure. The vehicle was not repaired. The failure mileage was 500.

- Toivola, MI, USA

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