2021 Subaru Forester Reliability Report

Stalling is the main complaint. The engine dies at lights and stop signs when start/stop fails to restart, and some cars lose power for several seconds while driving, with one total shutdown at 70 MPH on a highway. Dealers often find no codes. A second pattern involves the thermo control valve, a known problem addressed by a service bulletin, and one car burned shortly after that repair. Another fire followed a deer strike. Carbon buildup on the intake valves at 38,000 miles is also blamed for surging.

The glass splits while the car is moving, usually starting at an edge and running toward the center or across the driver's view. Some cracks begin small or as micro-fractures and spread overnight. Failure mileages range from about 1,900 to about 34,350, with many under 10,000. Replacement windshields sometimes crack again in the same spot, and one owner is on a third. Dealers often call it road damage or refer owners to insurance, and the manufacturer rarely helps, though one owner was offered reimbursement of the insurance copay.

Start/stop fails on an incline, letting the car roll back into a collision. Some cars surge forward when shifted into drive or while parking, and one rolled down a driveway while in park. Thermo control valve failures trigger a check engine light, disable EyeSight, and leave the engine unable to warm up, with one engine failing at 65,000 miles afterward. Other reports include a transmission replaced at 26,000 miles, a valve body at 40936, and hesitation or shudder that dealers cannot diagnose without trouble codes.

Unintended acceleration happens at parking-lot speeds. Cars lunge forward while pulling into a space, sometimes with the brake pressed, or surge backward when shifted into reverse. Four complaints involve crashes, including one where the car went over a wall into a ravine, and collision-avoidance features did not activate. Some drivers report repeat episodes days apart and engines revving on their own. Dealers typically run codes, find nothing, and cannot duplicate the problem. Reported mileages are low, around 7,000 to 24,000.

Front lower control arm bushings crack and tear, producing a clunk from the front end. In one case the dealer tried an ECU reprogram that did not stop the noise, and an independent shop replaced the bushings after a 37,000-mile inspection. Other reports describe the rear sway bar fracturing and detaching from the subframe at low speed, failing again after a bolt replacement, and a strut top bolt falling out, collapsing the wheel and bending the drive axle. Complaints are few, but the failures are serious.

Lane Keep Assist reportedly steers sharply toward a highway wall at about 75 mph, causing a crash and a minor head injury. Other reports describe the car shutting down in traffic with the steering locked, warning lights on, and constant beeping. Auto start/stop is blamed for cutting all power, with repeated shutdowns over a few days and no working hazard lights. The complaint count is small, but each describes a loss-of-control or stranded-in-traffic risk.

No air bag failure is described in either crash report. One gives no narrative beyond an attached document. The other describes the car hesitating repeatedly on light throttle while leaving a garage, then bolting forward, crossing the street, and striking a house. That account fits the unintended acceleration pattern reported elsewhere for this model year more than an air bag defect.