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 there's a problem with the part of the engine that helps control how much fuel goes into cylinder number 5. It's like a switch that is stuck in the 'on' position when it shouldn't be.
The Engine Control Module (ECM) has detected a high voltage signal from the low side circuit of the high-pressure injector for cylinder 5, indicating a potential electrical issue.
P3118 indicates that the ECM has detected an abnormally high voltage condition in the low side circuit of the high-pressure fuel injector for cylinder 5. This could be due to a short circuit, an open circuit, or a faulty injector driver within the ECM.
• Engine misfire
• Poor fuel economy
• Check Engine Light illuminated
• Faulty fuel injector for cylinder 5
• Wiring issues such as short to voltage in the injector circuit
• Faulty ECM or injector driver
ECM: Engine Control Module, the computer that controls engine functions.
Injector: A component that sprays fuel into the engine's cylinders.
• Perform a visual inspection of the injector wiring for cylinder 5.
• Use a multimeter to check for continuity and shorts in the wiring.
• Test the injector for proper operation.
• Repair or replace damaged wiring in the injector circuit.
• Replace the faulty injector.
• Replace or repair the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance and inspection of fuel system components.
• Use high-quality fuel to prevent injector clogging.
• Ensure proper electrical connections and avoid exposure to moisture.
Engine Performance
• Avoid driving the vehicle until the issue is diagnosed and repaired to prevent further damage.
• Consult a professional mechanic for accurate diagnosis and repair.
Check with the vehicle manufacturer for any applicable warranty coverage for engine components.
This code is relatively uncommon and may be specific to certain vehicle models with direct fuel injection systems.
Moderate – It is advisable to address this issue promptly to avoid potential engine damage.
Driving with a malfunctioning injector can lead to increased emissions and may not comply with local emissions regulations.
• Engine at operating temperature
• Vehicle in a safe location for testing
The high-pressure injector for cylinder 5 is located on the engine block, typically near the intake manifold.
Q: Can I drive with a P3118 code?
A: It is not recommended to drive with this code as it can lead to further engine damage and poor performance.
Q: How can I prevent injector issues?
A: Regular maintenance, using high-quality fuel, and ensuring electrical connections are secure can help prevent injector issues.
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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.
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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.