P0308 Code - Cylinder 8 Misfire Detected
Quick Answer
The Engine Control Module (ECM) uses information from the crankshaft position sensor and the camshaft position sensor to determine when an engine cylinder misfire is occurring. 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 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.
Code P0308 Description
Extreme cylinder misfire events can cause catalytic converter damage. The malfunction indicator lamp (MIL) will flash when the conditions for catalytic converter damage are present. The Diagnostic Trouble Codes (DTC) P0308 correspond to cylinders 8. When the ECM detects that one or more specific cylinders are misfiring, the DTC for the respective misfiring cylinder will set, and up to 2 of the corresponding fuel injectors are disabled for a minimum of 30 s. The ECM will then re-enable the fuel injector and, after approximately 200 engine revolutions, will determine if the misfire is still present. If the misfire is still present, the ECM will disable the fuel injector again repeating the process. If the misfire is not present, the fuel injector will remain enabled by the ECM. In Spark Ignition Direct Injection (SIDI) system applications, if a fuel injector fault DTC is set during a misfire event, the ECM will not re-enable the injector.
What are the Possible Causes of the DTC P0308?
- 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?
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
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What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0308 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 Makes
- P0308 Audi — Cylinder 8 Misfire Condition
- P0308 Buick — Cylinder 8 Misfire Detected
- P0308 Cadillac — Cylinder 8 Misfire Detected
- P0308 Chevrolet — Cylinder 8 Misfire Detected
- P0308 Chrysler — Cylinder 8 Misfire Detected
- P0308 Dodge — Cylinder 8 Misfire Detected
- P0308 Ford — Cylinder 8 Misfire Detected
- P0308 GMC — Cylinder 8 Misfire Detected
- P0308 Hummer — Cylinder 8 Misfire Detected
- P0308 Infiniti — Number 8 Cylinder Misfire Detected
- P0308 Jeep — Cylinder 8 Misfire Detected
- P0308 KIA — Cylinder 8 Misfire Detected
- P0308 Lexus — Cylinder 8 Misfire Detected
- P0308 Lincoln — Cylinder 8 Misfire Detected
- P0308 Mercedes-Benz — Cylinder 8 Misfire Detected
- P0308 Mercury — Cylinder 8 Misfire Detected
- P0308 Mitsubishi — Cylinder 8 Misfire Condition
- P0308 Nissan — Number 8 Cylinder Misfire Detected
- P0308 Oldsmobile — Cylinder 8 Misfire Detected
- P0308 Pontiac — Cylinder 8 Misfire Detected
- P0308 Ram — Cylinder 8 Misfire Detected
- P0308 Toyota — Cylinder 8 Misfire Detected
- P0308 Volkswagen — Cylinder 8 Misfire Condition
Frequently Asked Questions about P0308 Code
1. What are the common symptoms of OBDII code P0308 (Cylinder 8 Misfire Detected)?
- Common symptoms include rough idling, engine hesitation, loss of power, and increased fuel consumption.
2. What are the possible causes of OBDII code P0308?
- Potential causes of this code include faulty ignition system components, a clogged fuel injector, vacuum leaks, or low compression in the cylinder.
3. How can I diagnose the cause of a misfire in cylinder 8?
- Diagnose by checking spark plugs, ignition coils, fuel injectors, compression levels, and performing a visual inspection for vacuum leaks.
4. What are some repair tips for addressing OBDII code P0308?
- Repair tips include replacing faulty spark plugs, ignition coils, or fuel injectors, fixing vacuum leaks, and performing a compression test to identify engine issues.
5. Can driving with OBDII code P0308 cause further damage to the vehicle?
- Continued driving with a misfire can potentially lead to damage to the catalytic converter, O2 sensors, or other engine components, so it's best to address the issue promptly.
6. How much does it typically cost to repair OBDII code P0308?
- The cost of repairs can vary depending on the root cause of the misfire, but it may range from a few hundred to over a thousand dollars, including parts and labor.
7. Is it safe to drive my vehicle with OBDII code P0308?
- It is not recommended to drive the vehicle with a misfire as it can lead to further damage and potentially unsafe driving conditions.
8. Can bad gasoline cause OBDII code P0308 to trigger?
- Poor quality or contaminated gasoline could contribute to a misfire issue, but it is usually not the sole cause. It's important to rule out other potential factors through proper diagnosis.
9. How long does it take to repair OBDII code P0308?
- The repair time can vary depending on the specific cause of the misfire, but it may take a few hours to a full day for diagnostics and repairs to be completed.
10. Will resetting the OBDII code P0308 clear the issue permanently?
- Simply clearing the code without addressing the underlying cause will not fix the issue permanently. It's crucial to identify and resolve the root cause of the misfire.
Discuss the causes and fixes for P0308 OBDII Code
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where's the location of the #8 spark plug on a 2002f150-5.4, I wanna clear code PO308 & PO316
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