Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the electrical part that controls how much fuel goes into the engine for cylinder number 4. It's like a light switch stuck in the 'on' position, letting too much electricity through.
The P21E3 code is triggered when the Engine Control Module (ECM) detects a high voltage condition in the injector circuit for cylinder 4. This can indicate an issue with the wiring or the injector itself.
The P21E3 code indicates that the ECM has detected a higher than expected voltage in the injector B circuit for cylinder 4. This could be due to a short circuit, an open circuit, or a malfunctioning injector. The injector is responsible for delivering fuel into the engine's combustion chamber, and a high circuit condition can affect engine performance.
• Check Engine Light is on
• Poor engine performance
• Increased fuel consumption
• Faulty fuel injector
• Open or shorted injector wiring
• Poor electrical connection in the injector circuit
ECM: Engine Control Module
Injector: A device that sprays fuel into the engine's combustion chamber
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the injector for proper resistance and operation.
• Replace the faulty injector.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the repair was successful.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and maintain the fuel system.
• Ensure electrical connections are clean and secure.
• Use quality fuel to prevent injector clogging.
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regular maintenance can prevent such issues.
Injector issues may be covered under the powertrain warranty. Check with your vehicle manufacturer.
Injector circuit issues have been common in vehicles with high mileage or poor maintenance.
Moderate – While the vehicle may still be drivable, it can lead to further engine damage if not addressed.
Driving with a malfunctioning injector can lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Vehicle stationary
The fuel injector for cylinder 4 is located on the engine block, typically under the intake manifold.
Q: Can I drive my car with a P21E3 code?
A: Driving with this code is not recommended as it may cause further engine damage.
Q: How can I prevent injector issues?
A: Regular maintenance and using quality fuel can help prevent injector issues.
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