P1491 Honda Code - Exhaust Gas Recirculation Valve Insufficient Lift
Quick Answer
The Exhaust Gas Recirculation (EGR) system reduces Oxides of Nitrogen (NOx). Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, Exhaust Gas Recirculation Valve harness is open or shorted, Exhaust Gas Recirculation Valve circuit poor electrical connection. Severity is Moderate - service should be scheduled soon. The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
- What it means
- P1491 Honda indicates Exhaust Gas Recirculation Valve Insufficient Lift.
- Common causes
- Common causes include Faulty Exhaust Gas Recirculation (EGR) Valve, Exhaust Gas Recirculation Valve harness is open or shorted, Exhaust Gas Recirculation Valve circuit poor electrical connection.
- Severity
- Moderate - service should be scheduled soon.
- Can I drive?
- The vehicle may still be drivable for short trips if it runs normally, but avoid hard driving and repair it soon.
Code P1491 Honda Description
The EGR system lowers peak combustion temperature by recirculating inactive exhaust gas into the air/fuel mixture, thus reducing NOx emissions.
The EGR valve position sensor is built into the EGR valve and detects the amount of valve lift. The command value for the target valve lift is previously stored in the Powertrain Control Module (PCM) so that exhaust gas recirculation can be optimized according to driving conditions.
Comparing this command value with the EGR valve position sensor output signal value, the PCM controls the EGR valve to make the amount of actual valve lift equal to the command value.
If the EGR valve position sensor output signal value differs greatly from the command value in the PCM memory for a set period of time, the EGR valve or the EGR valve position sensor is considered faulty and a DTC is stored.
What are the Possible Causes of the DTC P1491 Honda?
- Faulty Exhaust Gas Recirculation (EGR) Valve
- Exhaust Gas Recirculation Valve harness is open or shorted
- Exhaust Gas Recirculation Valve circuit poor electrical connection
- Exhaust Gas Recirculation Valve clogged
- Exhaust gas leaks
How to Fix the DTC P1491 Honda?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
Code Tech Notes
User Submitted Video
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P1491 Honda code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
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Information for Specific Honda Models
- P1491 1996 Honda Civic — Exhaust Gas Recirculation Valve Insufficient Lift
- P1491 1997 Honda Civic — Exhaust Gas Recirculation Valve Insufficient Lift
- P1491 1998 Honda Civic — Exhaust Gas Recirculation Valve Insufficient Lift
- P1491 1999 Honda Civic — Exhaust Gas Recirculation Valve Insufficient Lift
- P1491 2000 Honda Civic — Exhaust Gas Recirculation Valve Insufficient Lift
Frequently Asked Questions about P1491 Honda Code
1. What are common symptoms of OBDII code P1491 in a Honda related to the Exhaust Gas Recirculation (EGR) Valve Insufficient Lift?
The common symptoms include rough idling, engine stalling, decreased fuel efficiency, and the illumination of the Check Engine light.
2. What are the potential causes of OBDII code P1491 in a Honda indicating Exhaust Gas Recirculation (EGR) Valve Insufficient Lift?
Possible causes include a faulty EGR valve, blocked EGR passages, a malfunctioning EGR solenoid, or issues with the EGR sensor.
3. How can I diagnose OBDII code P1491 in my Honda that points to Exhaust Gas Recirculation (EGR) Valve Insufficient Lift?
Diagnosis typically involves checking the EGR valve for proper operation, inspecting the EGR passages for blockages, testing the EGR solenoid, and checking the EGR sensor's functionality.
4. What are some repair tips for addressing OBDII code P1491 in a Honda with Exhaust Gas Recirculation (EGR) Valve Insufficient Lift?
Repair tips may include cleaning or replacing the EGR valve, clearing any blockages in the EGR passages, testing and replacing the EGR solenoid if necessary, and ensuring proper functioning of the EGR sensor.
5. Can driving with OBDII code P1491 related to Exhaust Gas Recirculation (EGR) Valve Insufficient Lift cause further damage to my Honda?
Continued driving with this issue may lead to reduced engine performance, increased emissions, and potential damage to other engine components over time. It is recommended to address the problem promptly.
6. How much does it typically cost to repair OBDII code P1491 in a Honda caused by Exhaust Gas Recirculation (EGR) Valve Insufficient Lift?
The cost of repair can vary depending on the specific issue, but it may range from $100 to $500 or more, including parts and labor.
7. Can I reset OBDII code P1491 related to Exhaust Gas Recirculation (EGR) Valve Insufficient Lift in my Honda using a diagnostic tool?
Yes, you can reset the code using an OBDII scanner or diagnostic tool after addressing the underlying issue with the EGR system. This will clear the Check Engine light and monitor the system for any recurring problems.
8. How long does it take to fix OBDII code P1491 caused by Exhaust Gas Recirculation (EGR) Valve Insufficient Lift in a Honda?
The repair time can vary based on the specific cause of the issue and the complexity of the repair. It may take anywhere from 1 to 4 hours or more to complete the necessary repairs.
9. Is it safe to continue driving my Honda with OBDII code P1491 indicating Exhaust Gas Recirculation (EGR) Valve Insufficient Lift?
While the vehicle may still be operational with this code, it is recommended to address the underlying issue promptly to prevent potential engine damage, reduced performance, and increased emissions.
10. Are there any preventive measures I can take to avoid OBDII code P1491 related to Exhaust Gas Recirculation (EGR) Valve Insufficient Lift in my Honda in the future?
Regular maintenance, such as cleaning the EGR system components during scheduled services, can help prevent issues leading to code P1491. Additionally, using high-quality fuel and following recommended driving practices can contribute to the EGR system's longevity.
Discuss the causes and fixes for P1491 Honda OBDII Code
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I have a check engine light on the code is p1491 should I replace the EGR valve?
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What model and year is your Honda? you could start by inspecting for exhaust leaks. If no leaks are present, then the next step is to clean the EGR valve. Carbon deposits could clog up the EGR valve and passage.
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For a 2003 Honda Civic EX could an exhaust leak be pulling up code p1491? Potentially causing some hesitation as well? Thanks!
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i have a huge hole in my exhaust its basically open headers could i say that is most likely the reason for the code
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Yes, it's very likely that the problem is the exhaust leak. If that is not the problem, you can't properly diagnose the problem with the exhaust leak.
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Hi i have a few questions i am having a hard time passing emmissions for my car Honda Accord 1998 Ex 6 cylinder
P1491 MANUFACTURER SPECIFIC CODE
P0420 CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD BANK 1
P0401 EXHAUST GAS RECIRCULATION A FLOW INSUFFICENT DETECTEDPLEASE HELP
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If you clear all the codes, what code comes back first? More than likely you have to replace the EGR valve to start, but start by checking the EGR passages, make sure the holes are clean of carbon. Carbon built up could cause poor re-circulation.
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I have a 2000 Honda Accord giving me a P1491 code. I have replaced the egr valve and cleaned all the ports. Car has over 200,000 miles on it. What next?
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Do you have 4 or 6 cylinders? did you remove the intake to clean the ports? If you have 6 cylinder engine, you may have to drill out all the carbon built up.
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I Have a 1997 Honda accord i Have This code p1491 coming up , when my check engine light comes on , i have cleaned the EGR Valve , So I Have No Idea What Else It Could Be Because My Car Idolizes When im in park or even at a stop light & that is the knlh code that comes out
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I got a 99 accord V6 coupe, and im getting a P1491 code, i removed the intake and cleaned the ports, even tho there was no carbon deposits inside, and i had removed the egr itself and cleaned the passage and the egr itself, and still getting the code. What do i do now?
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If the valve and port are clean, then the most likely cause of the problem is the Exhaust Gas Recirculation (EGR) Valve. The valve may be sticking, not opening all the way and triggering the P1491 code.
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... recently bought a 1999 Honda Accord EX ... code showed up P1491 which is the EGR valve issue and i believe is a "Lift" problem ... is that true or does that code also mean something else?
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Yes, the valve is not lifting (open) enough. You could try removing and cleaning the valve, but if the problem continuous, the you may have to replace the valve.
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02 honda accord P1491 clean the port change the egr valve still gets the P1491 error what is next to get rid of the error ? that you for any help you can give me
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Does the engine stall when you manually lift the EGR diaphragm? If the engine does not stall the problem is a restricted EGR passage. If the engine stalls, and since you have already replaced the valve, then problem is either the wire to the ECM or the ECM itself.
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