AutoCodes – Ford – P0308 Ford

P0308 Ford Code - Cylinder 8 Misfire Detected

Quick Answer

Misfire is defined as a lack of combustion in a cylinder due to the absence of a spark, incorrect fuel metering, low compression, or any other cause. Common causes include Faulty spark plug 8, Clogged or faulty fuel injector 8, Faulty ignition coil 8. 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: P0308 Ford indicates Cylinder 8 Misfire Detected.
Common causes: Common causes include Faulty spark plug 8, Clogged or faulty fuel injector 8, Faulty ignition coil 8.
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 56,191

How popular is this code, among other codes? Medium

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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Table of contents Created and updated by William Orellana on Apr 09, 2023

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
FAQs
Comments
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Code P0308 Ford Description

Misfire is defined as a lack of combustion in a cylinder due to the absence of a spark, incorrect fuel metering, low compression, or any other cause.
When a misfire occurs, engine speed will fluctuate. If the engine speed fluctuates enough to cause the Crankshaft Position (CKP) sensor signal to vary, the Engine Control Module (ECM) can determine that a misfire is occurring.
The Malfunction Indicator Lamp (MIL) blinks once per second when detecting a misfire severe enough to cause catalyst damage. If the MIL is in a steady state due to a misfire, this indicates the threshold for emissions was exceeded and caused the vehicle to fail an inspection and maintenance tailpipe test.
This Diagnostic Trouble Code (DTC) sets when the misfire detection monitor detects an engine misfire in cylinder 8.

OBDII Code P0308 Ford - Cylinder 8 Misfire Detected - AutoCodes.com — P0308 Ford Code - Cylinder 8 Misfire Detected

What does this mean?

What are the Possible Causes of the DTC P0308 Ford?

Faulty spark plug 8
Clogged or faulty fuel injector 8
Faulty ignition coil 8
Fuel injector 8 harness is open or shorted
Fuel injector 8 circuit poor electrical connection
Ignition coil 8 harness is open or shorted
Ignition coil 8 circuit poor electrical connection
Insufficient cylinder 8 compression
Incorrect fuel pressure
Intake air leak

How to Fix the DTC P0308 Ford?

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 does this mean?

Code Tech Notes

The P0308 code means that cylinder #8 is misfiring or is randomly misfiring. Start by checking for intake leaks and if no leaks are found the next step is to replace the spark plugs on cylinder #8. If the problem persists more tests need to be done to diagnose the problem. See "Possible Causes" for the most common problems.

There is a Factory Service Bulletin for the 2011 Ford Mustang:
2011 Ford Mustang Factory Service Bulletin OBDII Code P0308
The Factory Service Bulletin recommends reprogramming the Powertrain Control Module (PCM) to resolve the problem.

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What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0308 Ford 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 P0308 Ford code?

Need more information on how to fix the P0308 Ford code? Get Access to Factory Service Manuals

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Get the P0308 Ford code diagnosed by a professional: Find a repair shop in your area

Information for Specific Ford Models

P0308 1997 Ford F150 — Cylinder 8 Misfire Detected
P0308 1998 Ford F150 — Cylinder 8 Misfire Detected
P0308 1999 Ford F150 — Cylinder 8 Misfire Detected
P0308 2000 Ford F150 — Cylinder 8 Misfire Detected
P0308 2001 Ford F150 — Cylinder 8 Misfire Detected
P0308 2002 Ford F150 — Cylinder 8 Misfire Detected
P0308 2003 Ford F150 — Cylinder 8 Misfire Detected

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 P0308 Ford Code

1. What are the common symptoms of OBDII code P0308 in a Ford, indicating a Cylinder 8 misfire detected?

The common symptoms include engine vibration, loss of power, rough idle, and potential stalling.

2. What are some possible causes of OBDII code P0308 in a Ford, signaling a Cylinder 8 misfire?

Potential causes may include faulty spark plugs, a malfunctioning ignition coil, low compression in cylinder 8, or a vacuum leak.

3. How can I diagnose the cause of OBDII code P0308 in a Ford related to a Cylinder 8 misfire?

You can perform a thorough inspection of the spark plugs, ignition coil, and compression in cylinder 8, as well as check for any vacuum leaks in the system.

4. What are some essential repair tips for addressing OBDII code P0308 in a Ford due to a Cylinder 8 misfire?

Ensure proper spark plug replacement, test and potentially replace the ignition coil, conduct a compression test on cylinder 8, and inspect for any vacuum leaks.

5. Can driving with OBDII code P0308 in a Ford, which signifies a Cylinder 8 misfire, cause further damage to the vehicle?

Continued driving with a misfire can potentially lead to damage to the catalytic converter or other engine components, so it is best to address the issue promptly.

6. How much does it typically cost to repair OBDII code P0308 in a Ford associated with a Cylinder 8 misfire?

The cost of repair can vary depending on the specific cause of the misfire, but it may range from a few hundred to over a thousand dollars, including parts and labor.

7. Are there any preventive measures to avoid encountering OBDII code P0308 in a Ford due to a Cylinder 8 misfire in the future?

Regular maintenance, such as changing spark plugs at recommended intervals, ensuring proper ignition system function, and addressing any engine performance issues promptly, can help prevent misfires.

8. Can weather conditions or driving habits contribute to triggering OBDII code P0308 in a Ford related to a Cylinder 8 misfire?

Extreme weather conditions, such as very cold temperatures, or aggressive driving habits that put additional stress on the engine, can potentially contribute to misfires.

9. Should I reset the OBDII code P0308 in a Ford after addressing the Cylinder 8 misfire issue?

After addressing the underlying cause of the misfire, it is recommended to clear the trouble code using an OBDII scanner to reset the system and monitor for any recurrence.

10. Is it advisable to continue driving my Ford if the check engine light is on due to OBDII code P0308 indicating a Cylinder 8 misfire?

It is generally not recommended to drive the vehicle for an extended period with a misfire, as it can lead to further damage and potentially unsafe driving conditions.