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 is having trouble figuring out how much fuel to send to the engine. It's like when you can't decide how much water to pour into a glass.
The engine control module (ECM) is not getting the expected signals from the fuel injectors on Bank 1, which affects fuel delivery.
The P31E8 code is triggered when the ECM detects a discrepancy between the expected and actual fuel delivery from the high-pressure injectors on Bank 1. This can be due to issues with the fuel injectors, fuel pressure, or ECM programming.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty high-pressure fuel injector
• Fuel pressure issues
• ECM software or calibration error
ECM: Engine Control Module
Fuel Injector: A component that sprays fuel into the engine's cylinders
• Perform a diagnostic scan to confirm the code
• Inspect the fuel injectors for proper operation
• Check fuel pressure levels
• Replace faulty fuel injector
• Repair or replace fuel pressure regulator
• Update or reprogram the ECM
• OBD-II scanner
• Fuel pressure gauge
• Multimeter
$200 - $800
Moderate
• Toyota Camry
• Honda Accord
• Ford Fusion
• Regular maintenance of fuel system
• Use high-quality fuel
• Keep ECM software updated
Engine Performance
• Do not ignore the Check Engine Light
• Get the vehicle inspected by a professional
• Avoid driving under heavy load conditions until fixed
Check with the vehicle manufacturer for warranty coverage on ECM and fuel system components.
This code has been reported in vehicles with direct fuel injection systems, particularly in models with high-pressure fuel systems.
Moderate – It should be addressed soon to avoid further engine performance issues.
Driving with this code may lead to increased emissions and fuel consumption.
• Engine at operating temperature
• Vehicle in closed-loop fuel control
The high-pressure fuel injectors are located on the engine, typically on the intake manifold side.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to poor engine performance and increased fuel consumption.
Q: Can I drive my car with this code?
A: While the car may still be drivable, it is recommended to fix the issue to prevent further damage.
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