Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a problem with the ignition coil for cylinder number 4, which is like a little transformer that helps the engine start. It's having trouble because there's too much resistance, like when you try to suck a thick milkshake through a straw.
The ignition coil for cylinder 4 is experiencing higher than normal electrical resistance, which can affect its ability to deliver the necessary spark to ignite the fuel-air mixture in the cylinder.
The P3307 code indicates that the ignition coil for cylinder 4 is experiencing contact resistance or high impedance. This can be due to poor electrical connections, corrosion, or a failing coil. The increased resistance can prevent the coil from generating a strong enough spark, leading to misfires and reduced engine performance.
• Engine misfire
• Rough idling
• Reduced fuel efficiency
• Faulty ignition coil
• Corroded or loose electrical connections
• Damaged wiring harness
Ignition Coil: A component that transforms the battery's voltage to a higher voltage needed to create a spark in the spark plugs.
Resistance: A measure of how much a component opposes the flow of electric current.
• Inspect the ignition coil for cylinder 4 for damage or wear.
• Check the electrical connections and wiring for corrosion or looseness.
• Test the resistance of the ignition coil with a multimeter.
• Replace the faulty ignition coil.
• Clean and secure any corroded or loose connections.
• Repair or replace damaged wiring.
• Multimeter
• Socket set
• Screwdriver
$100 - $300
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regularly inspect ignition coils and connections.
• Keep the engine bay clean to prevent corrosion.
• Follow the vehicle's maintenance schedule.
Engine Performance
• Have the vehicle inspected by a professional if you notice any symptoms.
• Avoid driving the vehicle with this issue for extended periods to prevent further damage.
Check with your vehicle manufacturer for warranty coverage on ignition components.
Ignition coil issues have been a common problem in vehicles with electronic ignition systems. Over time, coils can degrade due to heat and vibration.
Moderate – It's important to address this issue soon to prevent further engine damage.
Driving with a malfunctioning ignition coil can lead to increased emissions and may not comply with emissions regulations.
• Engine at operating temperature
• Vehicle stationary or at idle
The ignition coil for cylinder 4 is located on top of the engine, usually near the spark plug for that cylinder.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to engine misfires, reduced performance, and potentially more serious engine damage.
Q: Can I drive my car with this code?
A: While you may be able to drive the car, it's not recommended as it can cause further damage and affect performance.
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Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal repairs.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
View options on Amazon
Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.