Infiniti DTC P1491 – EGR Valve Lift Insufficient Detected
DTC P1491 meaning on Infiniti
- DTC P1491 indicates that the Engine Control Module (ECM) has detected insufficient EGR (Exhaust Gas Recirculation) valve lift.
Infiniti DTC P1491 symptoms
- Check Engine Light (CEL) illuminated on the dashboard.
- Reduced engine performance.
- Possible rough idling or stalling.
Infiniti DTC P1491 causes
- Malfunctioning EGR valve.
- Clogged EGR passages.
- Faulty EGR position sensor.
- Wiring or connector issues in the EGR system.
Infiniti DTC P1491 seriousness
- While the vehicle may still be operable with this issue, it can lead to reduced fuel efficiency and increased emissions.
- Continued driving with a malfunctioning EGR system can potentially cause damage to other engine components.
How to diagnose DTC P1491 on Infiniti
- Use a scan tool to retrieve the DTC and freeze frame data.
- Inspect the EGR valve and related components for any visible damage or blockages.
- Check the EGR position sensor for proper operation.
- Test the EGR system for vacuum leaks or electrical faults.
How to fix DTC P1491 on Infiniti
- Clean or replace the EGR valve if it is found to be faulty.
- Clean out any clogged EGR passages.
- Replace the EGR position sensor if necessary.
- Repair any wiring or connector issues in the EGR system.
How to erase DTC P1491 on Infiniti
- After the issue has been fixed, use a scan tool to clear the DTC and reset the Check Engine Light.
- Ensure that the repair has resolved the underlying problem causing the DTC.
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