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P0020ModeratePowertrain

P0020 on 2004-2021 Subaru WRX STI — Camshaft Position 'A' Actuator Circuit (Bank 2)

1 vehicles · 1 makes · $150-$500 repair

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Most Reported On

2004-2021Subaru WRX STI

P0020 is an OBD-II diagnostic trouble code meaning “Camshaft Position 'A' Actuator Circuit (Bank 2).” P0020 is a generic powertrain code indicating a fault in the camshaft position (intake/'A') actuator circuit on bank 2 — the side of the engine that does not contain cylinder number one. The engine computer controls a variable valve timing (VVT) solenoid to advance or retard camshaft timing for efficiency and power; this code sets when it detects an electrical problem in that solenoid's control circuit. The result can be reduced performance, rough running, or poor fuel economy. It is usually not an immediate breakdown risk but should be diagnosed to prevent driveability and timing issues. This code is most commonly reported on 2004-2021 Subaru WRX STI, with repair costs ranging from $150 to $500.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
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Common Causes

1Faulty bank 2 camshaft (VVT/oil control) solenoid
2Wiring or connector damage to the VVT solenoid
3Low or dirty engine oil restricting VVT operation
4Clogged VVT solenoid screen/oil passage
5Open or short in the actuator control circuit
6Failed PCM/ECM (rare)

Typical Repair Cost

$150 - $500

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P0020, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
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Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
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Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
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Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
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Vehicles Affected (1)

Subaru P0020 page →
WRX STIModerate

AVCS Solenoid Failure (Variable Valve Timing)

2004-2021$150-$5000 reports

Related Codes (8)

P0021Intake Camshaft Position Timing - Over-Advanced (Bank 2)P0022Intake Camshaft Position Timing - Over-Retarded (Bank 2)P0024Exhaust Camshaft Position Timing - Over-Advanced (Bank 2)P0034Turbocharger/Supercharger Bypass Valve Control Circuit LowP0035Turbocharger/Supercharger Bypass Valve Control Circuit HighP003ATurbocharger/Supercharger Boost Control 'A' Position Exceeded Learning LimitP0046Turbocharger/Supercharger Boost Control 'A' Circuit Range/PerformanceP0089Fuel Pressure Regulator 1 Performance

FAQ

What does P0020 mean?

P0020 stands for "Camshaft Position 'A' Actuator Circuit (Bank 2)." P0020 is a generic powertrain code indicating a fault in the camshaft position (intake/'A') actuator circuit on bank 2 — the side of the engine that does not contain cylinder number one. The engine computer controls a variable valve timing (VVT) solenoid to advance or retard camshaft timing for efficiency and power; this code sets when it detects an electrical problem in that solenoid's control circuit. The result can be reduced performance, rough running, or poor fuel economy. It is usually not an immediate breakdown risk but should be diagnosed to prevent driveability and timing issues.

What are the most common causes of P0020?

The most common causes of P0020 are: Faulty bank 2 camshaft (VVT/oil control) solenoid, Wiring or connector damage to the VVT solenoid, Low or dirty engine oil restricting VVT operation, Clogged VVT solenoid screen/oil passage, Open or short in the actuator control circuit, Failed PCM/ECM (rare). The specific cause varies by vehicle.

How much does it cost to fix P0020?

Repair costs for P0020 range from $150 to $500, depending on the vehicle and root cause.

Which vehicles are affected by P0020?

Au7o has documented P0020 across 1 vehicle models from 1 manufacturers: Subaru.

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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Vehicle data and repair guidance on this site are compiled with AI assistance and may contain errors. Always verify with your service manual or a qualified mechanic.

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