Description
OBD-II Trouble Code Description for P0400 Mazda
Exhaust Gas Recirculation Flow
What does this mean?
OBD2 Code P0400 Mazda definition:
The exhaust gas recirculation (EGR) valve is vacuum controlled valve that regulates the amount of exhaust gases that re-enter the cylinders. The powertrain control module (PCM) determines how much based on engine load, temp, and other conditions. If the PCM detects that the amount of exhaust gases entering the cylinder were insufficient or non-existent, this code is set.
Symptoms
Possible sumptoms of OBD code P0400 Mazda
No symptoms will likely be noticed by the driver other than the MIL (malfunction indicator lamp). However, non visible symptoms will be increased combustion temperature and increased Nox emissions. Sometimes you may notice a flat spot, or the vehicle may enter limp mode or show a EML light.
Causes
Possible causes of OBD code P0400 Mazda
A code P0400 Mazda may mean that one or more of the following has happened: Plugged EGR passage which restricts the flow of exhaust gasses Faulty EGR solenoid Faulty EGR solenoid wiring/harness Vacuum lines damaged/disconnected to the EGR valve solenoid or to the EGR valve Faulty EGR valve
Possible Solutions
Since EGR valve designs are different, no one test will suffice: Using a scan tool, operate the EGR valve with the engine running. If the engine stumbles, the problem was likely intermittent wiring problem or intermittent blockage problem If engine doesn’t stumble, operate the EGR valve manually, if possible. If engine doesn’t stumble and die, the ports are likely plugged. Removal of valve and cleaning of all ports will be required Checking of solenoid can only usually be done with a scan tool, because most solenoids operate with a duty cycle of voltage, rather than constant voltage Check all vacuum lines, hoses, etc for any damage Visually inspect the solenoid harness and the solenoid for damage Replace EGR valve
The OBD2 Code Information Be Applicable For Mazda:
2013 Mazda MX-5,2013 Mazda CX-9,2013 Mazda CX-5,2013 Mazda 6,2013 Mazda 5,2013 Mazda 3,2012 Mazda CX-5,2012 Mazda BT-50,2012 Mazda 3,2011 Mazda 6,2011 Mazda 5,2011 Mazda 2,2010 Mazda CX-7,2010 Mazda 3,2009 Mazda RX-8,2009 Mazda MX-5,2009 Mazda CX9,2009 Mazda 6,2009 Mazda 2,2008 Mazda MX-5,2008 Mazda 6,2008 Mazda 5,2008 Mazda 2,2007 Mazda CX-9,2007 Mazda CX-7,2006 Mazda MX5,2006 Mazda 6,2006 Mazda 3,2005 Mazda Atenza,2005 Mazda 6,2004 Mazda MPV,2004 Mazda 6,2004 Mazda 5,2004 Mazda 3,2003 Mazda RX-8
Note:
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