AutoCodes – Honda – P1509 1997 Honda Civic

P1509 1997 Honda Civic Code - Idle Air Control Valve System High RPM

Quick Answer

The target idle speed is in the Engine Control Module (ECM) memory for various engine conditions (coolant temperature, A/C operation and so on). Common causes include Faulty Idle Air Control Valve, Idle Air Control Valve harness is open or shorted, Idle Air Control Valve circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1509 1997 Honda Civic indicates Idle Air Control Valve System High RPM.
Common causes: Common causes include Faulty Idle Air Control Valve, Idle Air Control Valve harness is open or shorted, Idle Air Control Valve circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 7,849

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Aug 25, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1509 1997 Honda Civic Description

The target idle speed is in the Engine Control Module (ECM) memory for various engine conditions (coolant temperature, A/C operation and so on). The ECM keeps the actual idle speed at the target idle speed by switching the Idle Air Control Valve IACV) ON/OFF to control the intake airflow. If the IACV output duty cycle (the length of ON time) is out of a specified range, a malfunction is detected and a DTC is stored.

OBDII Code P1509 1997 Honda Civic - Idle Air Control Valve System High RPM - AutoCodes.com — P1509 1997 Honda Civic Code - Idle Air Control Valve System High RPM

What does this mean?

What are the Possible Causes of the DTC P1509 1997 Honda Civic?

Faulty Idle Air Control Valve
Idle Air Control Valve harness is open or shorted
Idle Air Control Valve circuit poor electrical connection

How to Fix the DTC P1509 1997 Honda Civic?

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.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1509 1997 Honda Civic 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.

Need more information about the P1509 1997 Honda Civic code?

Need more information on how to fix the P1509 1997 Honda Civic code? Get Access to Factory Service Manuals

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P1509 1997 Honda Civic Code

1. What are the common symptoms of OBDII code P1509 in a 1997 Honda Civic?

The common symptoms include high idle RPM (revolutions per minute), erratic idle speed, stalling at idle, and potential engine hesitation.

2. What does OBDII code P1509 indicate in a 1997 Honda Civic?

Code P1509 indicates an issue with the Idle Air Control Valve (IACV) system, specifically high RPM operation.

3. What are the possible causes of OBDII code P1509 in a 1997 Honda Civic?

Possible causes include a faulty Idle Air Control Valve, dirty or clogged IACV passages, vacuum leaks, a malfunctioning throttle body, or issues with the engine's computer system.

4. How can I diagnose the cause of OBDII code P1509 in my 1997 Honda Civic?

Diagnosis typically involves checking the Idle Air Control Valve for proper operation, inspecting for vacuum leaks, cleaning the IACV and throttle body, and using a scan tool to monitor IACV operation.

5. Can I drive my 1997 Honda Civic with OBDII code P1509?

It is not recommended to drive the vehicle with code P1509 as it can lead to engine stalling and other drivability issues. It is best to address the problem promptly.

6. How can I repair OBDII code P1509 in my 1997 Honda Civic?

Repair options may include cleaning or replacing the Idle Air Control Valve, fixing any vacuum leaks, cleaning the IACV passages, ensuring proper throttle body operation, and resetting the engine control module.

7. Is it possible to clean the Idle Air Control Valve to fix OBDII code P1509 in my 1997 Honda Civic?

Yes, cleaning the Idle Air Control Valve and its passages can sometimes resolve the high RPM issue associated with code P1509. However, if the valve is faulty, it may need to be replaced.

8. How much does it typically cost to repair OBDII code P1509 in a 1997 Honda Civic?

The cost of repairs can vary depending on the root cause of the issue. Cleaning the IACV and related components may be relatively inexpensive, while replacing the valve or other parts could be more costly.

9. Can a DIY enthusiast fix OBDII code P1509 in a 1997 Honda Civic?

Depending on the individual's mechanical skills and access to tools, some DIY enthusiasts may be able to tackle the repairs associated with code P1509. However, it is recommended to follow proper diagnostic procedures to ensure an accurate fix.

10. Will resetting the check engine light resolve OBDII code P1509 in my 1997 Honda Civic?

Resetting the check engine light may temporarily clear the code, but it will not fix the underlying issue causing code P1509. It is essential to diagnose and address the root cause of the problem to prevent it from reoccurring.