P1491 – Acura DTC

Acura DTC P1491 – EGR Valve Lift Insufficient Detected

DTC P1491 meaning on Acura

DTC P1491 on an Acura indicates that the Engine Control Module (ECM) has detected insufficient EGR (Exhaust Gas Recirculation) valve lift during operation. The EGR system is responsible for recirculating a portion of the exhaust gases back into the intake manifold to reduce combustion temperatures and emissions. Insufficient EGR valve lift can lead to increased emissions and reduced engine efficiency.

Acura DTC P1491 symptoms

Symptoms of DTC P1491 on an Acura may include:

• Check Engine Light (MIL) illuminated
• Decreased engine performance
• Increased fuel consumption
• Rough idling or stalling

Acura DTC P1491 causes

Common causes of DTC P1491 on an Acura include:

• Malfunctioning EGR valve
• Clogged EGR passages
• Faulty EGR position sensor
• Wiring or connector issues in the EGR system

Acura DTC P1491 seriousness

While DTC P1491 may not cause immediate drivability issues, it can lead to increased emissions and reduced fuel efficiency. Ignoring this code can potentially cause long-term damage to the engine and emissions system.

How to diagnose DTC P1491 on Acura

To diagnose DTC P1491 on an Acura, you can perform the following steps:

1. Use an OBD-II scanner to retrieve the fault code and freeze frame data
2. Inspect the EGR valve and associated components for any visible damage or clogging
3. Check the EGR position sensor for proper operation
4. Test the EGR valve lift using a scan tool to ensure it is functioning within specifications
5. Inspect the wiring and connectors in the EGR system for any signs of damage or corrosion

How to fix DTC P1491 on Acura

To fix DTC P1491 on an Acura, you can try the following solutions:

1. Clean or replace the EGR valve if it is clogged or malfunctioning
2. Clean out any clogged EGR passages in the intake manifold
3. Replace the EGR position sensor if it is faulty
4. Repair any damaged wiring or connectors in the EGR system
5. Clear the fault code using an OBD-II scanner after making the necessary repairs

How to erase DTC P1491 on Acura

To erase DTC P1491 on an Acura, you can follow these steps:

1. Ensure that the underlying issue causing the fault code has been resolved
2. Use an OBD-II scanner to clear the fault code from the ECM’s memory
3. Start the vehicle and ensure that the Check Engine Light does not reappear

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