Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is saying that something is wrong with the part that helps put fuel into cylinder number 11. It's like when a light switch is stuck in the 'on' position, and it shouldn't be.
This code indicates that the electrical circuit controlling the fuel injector for cylinder 11 is experiencing higher than normal voltage, which could mean a wiring issue or a faulty injector.
The P31AD code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the low side circuit of the H2 injector for cylinder 11. This could be due to a short circuit, a faulty injector, or a problem with the ECM itself.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty injector
• Short circuit in the wiring
• Defective ECM
ECM: Engine Control Module
Injector: A device that sprays fuel into the engine
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for cylinder 11 injector.
• Test the injector for proper operation.
• Repair or replace damaged wiring.
• Replace the faulty injector.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Injector tester
$200 - $600
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance checks
• Ensure proper electrical connections
• Use quality fuel injectors
Engine Performance
• Do not ignore the Check Engine Light.
• Consult a professional mechanic for accurate diagnosis.
Check with your vehicle manufacturer for warranty coverage on fuel injectors.
This code is less common and usually associated with specific high-performance or specialized engines.
Moderate – It should be addressed soon to avoid potential engine damage.
Driving with this code may lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Vehicle on a level surface
The fuel injector for cylinder 11 is typically located on the engine block, near the intake manifold.
Q: Can I drive with a P31AD code?
A: It's not recommended to drive for long periods with this code, as it can lead to engine damage.
Q: What happens if I ignore this code?
A: Ignoring the code can result in poor engine performance and increased fuel consumption.
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