What is OBD-II Code P0317 – Rough Road Hardware Not Present

What is OBD-II Code P0317 – Rough Road Hardware Not Present?

If you are like most people, you dread seeing the check engine light turn on, but it’s a necessary evil. Your car’s onboard computer system, or OBD-II, constantly monitors your vehicle’s emission control system. If it detects a problem, it triggers a code and turns on the check engine light. One of those codes, OBD-II Code P0317 – Rough Road Hardware Not Present, indicates a misfire on startup when you’re driving on a smooth road. This article will give you the basics of what OBD-II Code P0317 is, what causes it, and how to fix it.

What does OBD-II Code P0317 mean?

OBD-II Code P0317 is a generic powertrain diagnostic trouble code, which means it applies to all vehicles equipped with OBD-II. It’s also known as “Rough Road Hardware Not Present” because it refers to a condition in which an engine misfires during startup when you’re driving on a relatively smooth road.

This code is triggered when the engine’s computer detects a misfire in one or more cylinders at startup while driving on a smooth road. The misfire can occur due to various reasons, including a dirty fuel injector or spark plug, a failing ignition coil, a vacuum leak, or a sensor failure.

What causes OBD-II Code P0317?

Several things can cause OBD-II Code P0317, and the list includes:

1. Failed spark plug
2. Failed ignition coil
3. Dirty fuel injector
4. Failed fuel injector
5. Vacuum leak
6. Sensor failure
7. Failing engine control module (ECM)

How do you diagnose OBD-II Code P0317?

Since OBD-II Code P0317 has multiple potential culprits, you’ll need to diagnose the specific root cause of the problem. Here are the common steps in diagnosing this issue:

1. Check for other codes: Before moving forward, check whether any other codes show up along with P0317. This information can give you an idea of related issues.

2. Test for rough road: Take your car on a bumpy road and check to see if the engine components misfire. This test helps to confirm whether the issue is the rough road hardware fault.

3. Check the spark plug: Failed spark plugs are commonly responsible for engine misfires. A technician has to check the functionality of each spark plug.

4. Check the fuel injector conditions: A clogged or dirty fuel injector can also cause an engine misfire. Check the fuel injector’s performance to ensure that this isn’t the root cause of the misfire.

5. Check the ignition coil condition: The ignition coil is responsible for transferring power to the spark plug. If it is weak or experiencing internal failure, it won’t generate a spark, leading to an engine misfire. Checking the ignition coil is relatively easy: you will require an ohmmeter to measure the coil’s resistance.

6. Check engine control module: If you have checked all the components listed above and the misfire problem persists, it may be caused by a damaged engine control module.

How do you fix OBD-II Code P0317?

After diagnosing the issue, repairing or replacing these components can fix OBD-II Code P0317. Below are some of the different solutions:

1. Replace spark plugs: A failed spark plug can be replaced or cleaned to solve the misfire problem.

2. Replace ignition coils: If the ignition coil is weak or experiencing internal failure, replace it to resolved this issue.

3. Clean fuel injectors: If the fuel injector is clogged or has deposits, consider cleaning the fuel system.

4. Replace fuel injectors: Failed fuel injectors must be replaced to restore vehicle performance.

5. Repair vacuum leak: A vacuum leak is easily repairable by a trained technician, and depending on the severity of the leak, it can be a simple or complicated fix.

6. Replace sensor: In case the technician discovers that the OBD-II sensor is responsible for the misfire, replacing it can solve the problem.

7. Replace the engine control module: If the ECU is damaged, the vehicle will need to be brought to a mechanic to have it replaced.

Frequently Asked Questions (FAQs)

1. Why did the check engine light come on with OBD-II Code P0317?
The check engine light comes on when the OBD-II detects a fault in the engine control systems.

2. Is it safe to drive with OBD-II Code P0317?
It isn’t safe to drive with OBD-II Code P0317. An engine misfire can cause expensive engine repairs if left unattended.

3. How much does it cost to fix OBD-II Code P0317?
The cost of repairs depends on the severity of the problem and location and quality of repair shops. Parts such as spark plugs and ignition coils are usually cheap, but more significant repairs such as the engine control module can be expensive.

4. How often should I replace my car’s spark plugs?
The manufacturer recommends spark plug replacemen before or around 100,000 miles or as per performance requirements in the car handbook.

5. How can you prevent OBD-II Code P0317 from happening again?
Maintaining your car well is the key to avoiding OBD-II Code P0317. Simple things like changing your oil and air filter, keeping your tyres inflated to the correct pressure, checking your fuel system and electrical system, and fixing small issues quickly can help prevent significant problems.


OBD-II Code P0317 can be annoying, but it’s not the end of the world as long as it is diagnosed and fixed early. Preventive maintenance can avoid this issue, ensuring the car is running smoothly. Regular engine servicing is a surefire way to have maximum performance, experiencing fewer issues while driving. Consult a qualified and experienced mechanic if you are unsure what’s causing the error code to prevent damaging engine components.

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