P2012
Intake Manifold Runner Control Circuit Low (Bank 2)
- Severity
- Medium
- Driving
- Drivable — book it in
A fault in the intake manifold runner control circuit on bank 2 - a low reading, usually a short to earth or an open circuit. The module cannot operate the runner flaps, so they stay wherever they were and the engine loses part of its power delivery.
Possible causes
- CommonCarbon build-up seizing the runner flaps or their linkage
- CommonFailed actuator motor or vacuum diaphragm
- CommonSplit, perished or disconnected vacuum hose
- CommonBroken linkage or a detached flap
- PossibleCorroded connector or damaged wiring
- PossibleFailed position sensor giving a false reading
What you might notice
- Loss of low-speed torque or flat top-end power
- Rough idle
- Hesitation
- Worse fuel economy
- Smoke on a diesel
- Check engine light on
What to check, in order
- Check the vacuum hoses first on a vacuum-operated system - a split or disconnected hose is the most common cause and the cheapest to fix.
- Check the flaps and linkage move freely. Carbon seizing them is very common on a diesel used for short journeys, and cleaning is often the whole repair.
- Watch commanded against actual runner position on the live data screen through a sweep.
- Inspect the connector for corrosion and the actuator for damage.
Read this code from your own car
Plug an ELM327 adapter into the OBD-II port under the dashboard. Pin16 reads every stored, pending and permanent code, explains each one like this page does — offline, with no account — and shows what the car recorded when the fault was set.
Where this code sits
P00xxP01xxP02xxP03xxP04xxP05xxP06xxP07xxP08xxP09xxP0AxxP0BxxP0CxxP0DxxP0ExxP0FxxP10xxP11xxP12xxP13xxP14xxP15xxP16xxP17xxP18xxP19xxP1AxxP1BxxP1CxxP1DxxP1ExxP1FxxP20xxP21xxP22xxP23xxP24xxP25xxP26xxP27xxP28xxP29xxP2AxxP2BxxP2CxxP2DxxP2ExxP2FxxP30xxP31xxP32xxP33xxP34xxP35xxP36xxP37xxP38xxP39xxP3AxxP3BxxP3CxxP3DxxP3ExxP3Fxx
Fuel, air metering and auxiliary emission controls
P2000P2001P2002P2003P2004P2005P2006P2007P2008P2009P2010P2011P2012P2013P2014P2015P2016P2017P2018P2019P2020P2021P2022P2023P2024P2025P2026P2027P2028P2029P2030P2031P2032P2033P2034P2035P2036P2037P2038P2039P2040P2041P2042P2043P2044P2045P2046P2047P2048P2049P2050P2051P2052P2053P2054P2055P2056P2057P2058P2059P2060P2061P2062P2063P2064P2065P2066P2067P2068P2069P2070P2071P2075P2076P2077P2078P2079P2080P2081P2082P2083P2084P2085P2086P2087P2088P2089P2090P2091P2092P2093P2094P2095P2096P2097P2098P2099