Au7o mascotAu7o
Known IssuesDiagnose my car
  1. Au7o
  2. /
  3. Known Issues
  4. /
  5. P2016
P2016ModeratePowertrain

P2016: How to Diagnose & Fix — Intake Manifold Runner Position Sensor/Switch Circuit Low (Bank 1)

2 vehicles · 1 makes · $250-$1,400 repair

Share:@au7o.io

How to diagnose and fix P2016: most-reported vehicles

Ranked by owner reports. Each card gives the symptoms, how to confirm the cause, the fix, parts and sources for that vehicle.

Subaru WRX STI · 2004–2014

Community reported
110 owners
Link to this issueError Codes:P2004P2005P2011P2016

WRX STI models with EJ257 intake TGV assemblies can develop failures in the TGV position sensors or actuator mechanisms, leading to stuck-open/stuck-closed conditions. Owners report check engine lights, rough cold starts, and reduced drivability, especially in colder weather. This issue is frequently discussed in owner reports and appears in diagnostic guidance/TSBs for Subaru intake runner control/TGV-related DTCs.

Common Symptoms

  • Check Engine Light with TGV-related codes
  • Rough idle or stumbling on cold start
  • Reduced throttle response
  • Poor fuel economy
  • Intermittent hesitation at low RPM

How to Fix

Scan for TGV-related codes and verify actuator movement and sensor feedback; repair wiring/connectors as needed. Replace the affected TGV assembly or sensor/motor components and perform ECU relearn procedures per Subaru service manual; ensure no intake vacuum leaks after reassembly.

Typical repair cost:$250 - $1,400
Sources for this issue (1)
  • YouTube repair video covering Subaru TGV (tumble generator valve) issues/diagnosis and stuck-open/stuck-closed behavior (P2004/P2005/P2011/P2016 context)video

Research This Issue

Based on 110 owner reports

GoogleRedditYouTubeNHTSA
Community Reported
Medium Confidence110 owner reportsReviewed Apr 2026

Subaru WRX · 2008–2021

Link to this issueError Codes:P2004P2005P2006P2007P2016P2017

Turbo WRX intake manifolds carry tumble generator valves — butterfly plates in each runner driven by a small electric actuator with a position sensor. The original valve shaft material corrodes from EGR/condensation and binds, or the actuator motor/sensor fails, and the ECU logs TGV stuck-open/stuck-closed codes (P2004-P2007, sometimes P2016/P2017 position sensor codes). The car goes into a reduced-power mode. Subaru acknowledged the shaft corrosion in TSB 02-182-19 and revised the shaft material. It affects both the EJ255 (2008-2014) and FA20DIT (2015-2021) WRX, with separate part numbers per engine.

Common Symptoms

  • Check engine light with P2004-P2007
  • Significant loss of power / limp mode
  • Rough idle
  • Intermittent code that returns after clearing

How to Fix

Confirm by disconnecting the actuator and rotating the valve by hand — a gritty or stuck shaft means the TGV assembly is seized. Replace the affected TGV assembly with the revised-shaft part (Subaru does not sell the motor or sensor separately). Some owners delete TGVs with aftermarket housings, which requires a tune. Out of warranty there is no free remedy; the TSB is a diagnostic aid, not a campaign.

Typical repair cost:$350 - $1,200
Sources for this issue (3)
  • Tumble Generator Valve trouble - NASIOCforum
  • Intake Manifold Runner Control Stuck Open - ClubWRXforum
  • P2004 on 2015-2019 Subaru WRX: Tumble Generator Valve (TGV) Stuck Openarticle

Research This Issue

GoogleRedditYouTubeNHTSA
Community Reported
High ConfidenceVerifiedReviewed Sep 2026

Find P2016 by make

Browse every documented model and issue for your make.

Subaru · 2 issues

P2016 code reference

General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.

Frequently asked questions

What does P2016 mean?

P2016 stands for "Intake Manifold Runner Position Sensor/Switch Circuit Low (Bank 1)." This code indicates the engine computer detected a low-voltage signal (often a short to ground) from the intake manifold runner position sensor or switch on Bank 1. This sensor reports the position of the variable intake runner flaps. A persistently low signal tells the computer the sensor circuit is faulty and it can no longer confirm runner position, which can affect airflow optimization and emissions. It usually sets a check engine light and is generally not an immediate safety risk.

What are the most common causes of P2016?

The most common causes of P2016 are: Wiring shorted to ground in the sensor circuit, Faulty intake manifold runner position sensor, Corroded or damaged sensor connector, Carbon buildup affecting runner position feedback, Failed runner actuator, PCM circuit fault (rare). The specific cause varies by vehicle.

How much does it cost to fix P2016?

Repair costs for P2016 range from $250 to $1,400, depending on the vehicle and root cause.

Which vehicles are affected by P2016?

Au7o has documented P2016 across 2 vehicle models from 1 manufacturers: Subaru.

Related codes

  • P2010 · Intake Manifold Runner Control Circuit / Open (Bank 1)
  • P2011 · Intake Manifold Runner Control Circuit/Open (Bank 2)
  • P2014 · Intake Manifold Runner Position Sensor/Switch Circuit (Bank 1)
  • P2015 · Intake Manifold Runner Position Sensor/Switch Circuit Range/Performance (Bank 1)
  • P0020 · Camshaft Position 'A' Actuator Circuit (Bank 2)
  • P0034 · Turbocharger/Supercharger Bypass Valve Control Circuit Low
  • P0035 · Turbocharger/Supercharger Bypass Valve Control Circuit High
  • P003A · Turbocharger/Supercharger Boost Control 'A' Position Exceeded Learning Limit
🔧
A mechanic who knows YOUR exact car
Answers tuned to your year, make, model & trim — not generic advice. Save your garage so it always has the right context.
Get notified about P2016 fixes
We add new causes, fixes and affected vehicles for P2016 regularly — drop your email and we'll keep you posted. You can also diagnose your own car free.

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

Known IssuesMotorcycle IssuesDTC LookupDrivePricingAboutTermsPrivacyCookiesConsentData rightsCopyrightFeedback
Share:@au7o.io

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.

Data protection representation

DataRep representative in the United KingdomDataRep representative in the European Union
Au7o · 2026
Built for DIY mechanics. Privacy-first.

© 2026 Au7o. All rights reserved.