P2170
Exhaust Pressure Regulator Vent Solenoid Control Circuit Low
- Severity
- Medium
- Driving
- Drivable — book it in
A fault in the exhaust pressure regulator vent solenoid circuit - a low reading, usually a short to earth or an open circuit. The exhaust pressure regulator deliberately restricts the exhaust to raise back pressure, which warms the engine faster from cold and helps the particulate filter reach the temperature it needs. This solenoid vents the control pressure that operates it.
Possible causes
- CommonFailed vent solenoid
- CommonCorroded connector or damaged wiring
- CommonSplit, perished or disconnected vacuum hose
- CommonCarbon or soot seizing the regulator mechanism
- PossibleBlown fuse on the circuit
- RareFailed control module driver
What you might notice
- Reduced power or limp mode
- Slow to warm up in cold weather
- Excessive smoke on a diesel
- Poor cabin heating
- Particulate filter regeneration problems
- Check engine light on
What to check, in order
- Check the vacuum hoses first on a vacuum-operated system.
- Check the regulator mechanism moves freely - soot seizing it is common on a diesel used for short journeys.
- Measure the solenoid winding resistance against specification.
- Inspect the connector for corrosion and heat damage.
- Read all codes - particulate filter codes alongside this one matter more.
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 and air metering
P2100P2101P2102P2103P2104P2105P2106P2107P2108P2109P2110P2111P2112P2113P2114P2115P2116P2117P2118P2119P2120P2121P2122P2123P2124P2125P2126P2127P2128P2129P2130P2131P2132P2133P2134P2135P2136P2137P2138P2139P2140P2141P2142P2143P2144P2145P2146P2147P2148P2149P2150P2151P2152P2153P2154P2155P2156P2157P2158P2159P2160P2161P2162P2163P2164P2165P2166P2167P2168P2169P2170P2171P2172P2173P2174P2175P2176P2177P2178P2179P2180P2181P2182P2183P2184P2185P2186P2187P2188P2189P2190P2191P2192P2193P2194P2195P2196P2197P2198P2199