AutoCodes – Toyota – P0303 2016 Toyota RAV4

P0303 2016 Toyota RAV4 Code - Cylinder 3 Misfire Detected

Quick Answer

When the engine misfires, high concentrations of Hydrocarbons (HC) enter the exhaust gas. Common causes include Intake air leak, Faulty spark plug #3, Faulty ignition coil #3. 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: P0303 2016 Toyota RAV4 indicates Cylinder 3 Misfire Detected.
Common causes: Common causes include Intake air leak, Faulty spark plug #3, Faulty ignition coil #3.
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 378

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 25, 2022

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0303 2016 Toyota RAV4 Description

When the engine misfires, high concentrations of Hydrocarbons (HC) enter the exhaust gas. Extremely high hydrocarbon concentration levels can cause an increase in exhaust emission levels. Extremely high concentrations of hydrocarbons can also cause increases in the three-way catalytic converter temperature, which may cause damage to the three-way catalytic converter. To prevent this increase in emissions and to limit the possibility of thermal damage, the Engine Control Module (ECM) monitors the misfire count. When the temperature of the three-way catalytic converter reaches the point of thermal degradation, the ECM blinks the MIL. To monitor misfires, the ECM uses both the camshaft position sensor and the crankshaft position sensor. The camshaft position sensor is used to identify any misfiring cylinders and the crankshaft position sensor is used to measure variations in the crankshaft rotation speed. Misfires are counted when the crankshaft rotation speed variations exceed predetermined thresholds. If the misfire count exceeds the threshold levels and could cause emission control system performance deterioration, the ECM illuminates the MIL and stores a Diagnostic Trouble Code (DTC).

OBDII Code P0303 2016 Toyota RAV4 - Cylinder 3 Misfire Detected - AutoCodes.com — P0303 2016 Toyota RAV4 Code - Cylinder 3 Misfire Detected

What does this mean?

What are the Possible Causes of the DTC P0303 2016 Toyota RAV4?

Intake air leak
Faulty spark plug #3
Faulty ignition coil #3
Clogged or faulty fuel injector #3
Fuel injectors #3 harness is open or shorted
Fuel Injectors #3 circuit poor electrical connection
Ignition coils #3 harness is open or shorted
Ignition coils #3 circuit poor electrical connection
Incorrect Fuel pressure
Faulty Mass Air Flow (MAF) Sensor
Faulty Engine Control Module (ECM)
Faulty Engine Coolant Temperature (ECT) Sensor

How to Fix the DTC P0303 2016 Toyota RAV4?

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 P0303 code means that cylinder #3 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 #3. If the problem persists more tests need to be done to diagnose the problem. See "Possible Causes" for the most common problems.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0303 2016 Toyota RAV4 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 P0303 2016 Toyota RAV4 code?

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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 P0303 2016 Toyota RAV4 Code

1. What are the common symptoms of OBDII code P0303 on a 2016 Toyota RAV4?

- Common symptoms include engine misfire, rough idling, loss of power, increased fuel consumption, and potentially engine vibration.

2. What are the possible causes of a cylinder 3 misfire detected in a 2016 Toyota RAV4?

- The causes can range from a faulty spark plug or ignition coil, vacuum leaks, clogged fuel injector, to low compression in the cylinder.

3. How can I diagnose the source of the cylinder 3 misfire on my 2016 Toyota RAV4?

- Diagnostic steps may include inspecting spark plugs, checking ignition coils, testing fuel injectors, performing a compression test, and scanning for other related trouble codes.

4. Can driving with OBDII code P0303 on a 2016 Toyota RAV4 damage the engine?

- Continuing to drive with a misfire can potentially lead to damage to the catalytic converter, O2 sensors, or other engine components over time.

5. What is the typical repair process for addressing a cylinder 3 misfire in a 2016 Toyota RAV4?

- Repairs may involve replacing spark plugs, ignition coils, fuel injectors, addressing vacuum leaks, or performing engine compression repairs as needed.

6. Are there any maintenance tips to prevent OBDII code P0303 in a 2016 Toyota RAV4?

- Regular maintenance such as changing spark plugs, using quality fuel, keeping up with oil changes, and performing periodic engine tune-ups can help prevent misfires.

7. Can a DIY enthusiast fix OBDII code P0303 on a 2016 Toyota RAV4?

- Depending on their skill level, DIY enthusiasts may be able to address simpler causes like changing spark plugs, but more complex issues may require professional diagnosis and repair.

8. Is it safe to drive my 2016 Toyota RAV4 with a flashing check engine light due to a cylinder 3 misfire?

- A flashing check engine light indicates a severe misfire that can cause damage. It's advisable to pull over safely, address the issue, and avoid driving until the problem is fixed.

9. How much does it typically cost to repair OBDII code P0303 on a 2016 Toyota RAV4?

- Repair costs vary depending on the cause of the misfire, but expenses may include parts like spark plugs or ignition coils and labor for diagnosis and repair, ranging from $100 to $500 or more.

10. Can weather conditions or driving habits contribute to OBDII code P0303 in a 2016 Toyota RAV4?

- Extreme weather conditions, poor fuel quality, aggressive driving, or prolonged idling can potentially contribute to cylinder misfires in a vehicle.