AutoCodes – Oldsmobile – P0306 Oldsmobile

P0306 Oldsmobile Code - Cylinder 6 Misfire Detected

Quick Answer

A misfiring cylinder causes slight variations in the rotational speed of the crankshaft. Common causes include Faulty spark plug 6, Clogged or faulty fuel injector 6, Faulty ignition coil 6. 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: P0306 Oldsmobile indicates Cylinder 6 Misfire Detected.
Common causes: Common causes include Faulty spark plug 6, Clogged or faulty fuel injector 6, Faulty ignition coil 6.
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 1,339

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Aug 09, 2022

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0306 Oldsmobile Description

A misfiring cylinder causes slight variations in the rotational speed of the crankshaft. The Engine Control Module (ECM) can detect these variations by closely monitoring the crankshaft position sensor signal. The signals of the camshaft position sensors are used to determine which cylinder is misfiring. If the ECM detects a misfire rate sufficient to cause emission levels to exceed mandated standards, the Diagnostic Trouble Code (DTC) will be set. Under certain driving conditions, a misfire rate can be high enough to cause the catalytic converter to overheat, damaging the converter. The Malfunction Indicator Lamp (MIL) flashes when the converter is overheating, damaging conditions are present, and the DTC is set. The DTC will be set when the ECM detects a crankshaft rotation speed variation indicating a single-cylinder misfire rate sufficient to cause emissions levels to exceed mandated standards.

OBDII Code P0306 Oldsmobile - Cylinder 6 Misfire Detected - AutoCodes.com — P0306 Oldsmobile Code - Cylinder 6 Misfire Detected

What does this mean?

What are the Possible Causes of the DTC P0306 Oldsmobile?

Faulty spark plug 6
Clogged or faulty fuel injector 6
Faulty ignition coil 6
Fuel injector 6 harness is open or shorted
Fuel injector 6 circuit poor electrical connection
Ignition coil 6 harness is open or shorted
Ignition coil 6 circuit poor electrical connection
Insufficient cylinder 6 compression
Incorrect fuel pressure
Intake air leak

How to Fix the DTC P0306 Oldsmobile?

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 P0306 code means that cylinder 6 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 6. If the problem persists more tests need to be done to diagnose the problem, see "Possible Causes".

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0306 Oldsmobile 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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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 P0306 Oldsmobile Code

1. What are the common symptoms of OBDII code P0306 (Cylinder 6 Misfire Detected) in an Oldsmobile?

- Common symptoms include engine misfires, rough idling, loss of power, and possibly an illuminated check engine light.

2. What are some possible causes of a cylinder 6 misfire in an Oldsmobile triggering code P0306?

- Possible causes include faulty ignition coils, spark plugs, fuel injectors, vacuum leaks, low compression, or a problem with the engine's computer.

3. How can I diagnose the source of the misfire related to OBDII code P0306 in my Oldsmobile?

- Diagnosis typically involves checking spark plugs, ignition coils, fuel injectors, vacuum lines, compression levels, and performing a scan tool test for more specific information.

4. Can a dirty or clogged fuel injector cause a cylinder 6 misfire in an Oldsmobile?

- Yes, a dirty or clogged fuel injector can disrupt the proper fuel delivery to cylinder 6, leading to a misfire and triggering code P0306.

5. What are some recommended repair tips for addressing OBDII code P0306 in an Oldsmobile?

- Repair tips may include replacing faulty spark plugs, ignition coils, or fuel injectors, cleaning or flushing the fuel system, checking for vacuum leaks, and ensuring proper engine compression.

6. Is it safe to continue driving my Oldsmobile with OBDII code P0306 indicating a cylinder 6 misfire?

- It is not recommended to drive your vehicle with a misfire as it can lead to further damage to the engine components. It is best to address the issue promptly.

7. Can a bad ignition coil cause a misfire in cylinder 6 of an Oldsmobile, triggering code P0306?

- Yes, a faulty ignition coil can lead to a misfire in cylinder 6, causing the OBDII code P0306 to be triggered.

8. How important is it to address a cylinder 6 misfire detected by OBDII code P0306 in an Oldsmobile promptly?

- It is crucial to address a cylinder 6 misfire promptly to prevent potential damage to the catalytic converter, oxygen sensors, or other engine components.

9. What role does the engine's computer play in diagnosing and resolving OBDII code P0306 in an Oldsmobile?

- The engine's computer (ECU) monitors the performance of each cylinder and detects misfires. It provides valuable data for diagnosing and fixing the issue related to code P0306.

10. Are there any common mistakes to avoid when troubleshooting OBDII code P0306 (Cylinder 6 Misfire Detected) in an Oldsmobile?

- Common mistakes include neglecting basic maintenance tasks like changing spark plugs, assuming all misfires are caused by the same issue, and overlooking potential vacuum leaks.