Hard reset fixes problem temporarily?

2020 SUBARU FORESTER

30,000 MILES • 4WD • AUTOMATIC

KKINGERSOLL

MEMBER
2 POSTS

Multiple dash indicators and error codes all at once. Engine starts but when car is put in gear it jerks and shudders violently and won't drive above idle speed. WOT smooths out engine but drives about 10 mph.

RAB, EYESIGHT Check Engine, Lane Assist ect...
P26A6 Stored
P0222 Pending
P2004 Pending
P2005 Pending
P060B Pending
P2119 Pending
P0191 Pending
P26A6 Permanent
P2004 Permanent
P2005 Permanent
P24B9 Permanent
P26A3 Permanent

Car was sitting for 2 months. Battery voltage was 11 something. Charged overnight.

Performed a hard reset and car drove mostly normally with a bit of squirrely throttle. Parked and restarted an hour later and symptoms returned. Voltage holding at 12.43v with engine off.

Hard reset temporarily fixed the performance problems, did not reset dash indicators.

Aug 4, 2026 at 10:41 AM

KRAKENAUTO

✓Experienced Mechanic
73 POSTS

I am suspecting a low voltage, ground, or wiring/rodent issue, rather than all of these mechanical and electronic components failing at the same time.

When newer vehicles experience voltage drops, the Engine Control Module (ECM) and vehicle network freak out, setting a cascade of fault codes across multiple systems.

Your battery sat depleted for two months and very well could have permanently damaged the cells.

I'd first take the battery to an auto parts store for a load test, or test voltage during cranking. If it dips below 10V while cranking, replace the battery.

If it is the original battery or over 3-4 years old I'd replace either way.

Try this first and report back on your findings.

Aug 4, 2026 at 8:46 PM

KKINGERSOLL

MEMBER
2 POSTS

Replaced battery. Fixed all issues momentarily than within a less than a minute, symptoms returned. Car actually stalled when put into gear.

Aug 5, 2026 at 8:44 AM

STRAILER

✓Experienced Mechanic
55,214 POSTS

Hello, If I can add my 2 cents, I would clear the codes, then cycle the ignition switch off then on and don't crank the engine over and run the codes again, the idea is too see which codes come back, these will be the "hard codes" which we should address first.

P0222 – Throttle Position Sensor "B" Circuit Low
P2119 – Throttle Actuator Control Throttle Body Range/Performance
P0191 – Fuel Rail Pressure Sensor Range/Performance
P060B – Internal Control Module A/D Processing Performance
P2004 / P2005 – Intake Manifold Runner Control
P26A3 / P26A6 – Engine Coolant Bypass Valve
P24B9 – EVAP/Emission-related (varies slightly by Subaru calibration)

Let us know how it goes.

Aug 6, 2026 at 5:30 PM

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