Mazda DTC P1408 – EGR System Flow Out of Key On Engine Running Self Test Range
DTC P1408 meaning on Mazda
DTC P1408 on a Mazda indicates that the EGR (Exhaust Gas Recirculation) system flow is out of the key on engine running self-test range. This means that the EGR system is not functioning within the expected parameters during the self-test.
Mazda DTC P1408 symptoms
Symptoms of DTC P1408 on a Mazda may include:
- Check Engine Light (MIL) illuminated
- Decreased engine performance
- Increased fuel consumption
- Rough idling or stalling
Mazda DTC P1408 causes
Common causes of DTC P1408 on a Mazda include:
- Blocked EGR passages
- Malfunctioning EGR valve
- Wiring or connector issues in the EGR system
- PCM (Powertrain Control Module) software concerns
Mazda DTC P1408 seriousness
DTC P1408 should not be ignored as it can lead to reduced engine efficiency and increased emissions. Continuing to drive with this fault may cause further damage to the engine components over time.
How to diagnose DTC P1408 on Mazda
To diagnose DTC P1408 on a Mazda, a mechanic may perform the following steps:
- Use a scan tool to retrieve the fault code and freeze frame data
- Inspect the EGR system components for any visible damage or blockages
- Check the EGR valve operation and wiring connections
- Perform a vacuum test on the EGR valve
- Verify PCM software is up to date
How to fix DTC P1408 on Mazda
To fix DTC P1408 on a Mazda, the following steps may be taken:
- Clean or replace the EGR valve if necessary
- Clean out any blocked EGR passages
- Repair any damaged wiring or connectors in the EGR system
- Update the PCM software if required
How to erase DTC P1408 on Mazda
DTC P1408 can be erased on a Mazda using a scan tool that has the capability to clear fault codes. Once the underlying issue has been addressed and fixed, the code can be cleared to reset the Check Engine Light.
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