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 having trouble learning how much fuel to inject into cylinder 2.
The engine control module (ECM) is unable to learn the correct fuel injection timing for cylinder 2.
The P2B12 code indicates that the ECM has not successfully learned the injection pulse offset for cylinder 2. This learning process is crucial for optimizing fuel delivery and ensuring efficient engine performance. The failure to learn this offset can lead to suboptimal combustion in the affected cylinder.
• Check Engine Light is on
• Rough idling
• Decreased fuel efficiency
• Faulty fuel injector in cylinder 2
• Wiring issues in the fuel injector circuit
• ECM software or hardware malfunction
ECM: Engine Control Module, the computer that controls engine functions.
Fuel Injector: A device that sprays fuel into the engine's cylinders.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the fuel injector in cylinder 2.
• Test the fuel injector in cylinder 2 for proper operation.
• Repair or replace faulty wiring or connectors.
• Replace the fuel injector in cylinder 2 if defective.
• Reprogram or update the ECM software if necessary.
• OBD-II scanner
• Multimeter
• Fuel injector tester
$150 - $500
Moderate
• Chevrolet Cruze
• GMC Terrain
• Buick Encore
• Regular maintenance and inspection of fuel injectors.
• Ensure ECM software is up to date.
• Check and repair wiring issues promptly.
Engine Performance
• Have your vehicle inspected by a professional mechanic.
• Avoid driving long distances until the issue is resolved.
Check with your vehicle manufacturer for warranty coverage on ECM and fuel injectors.
This code has been reported in vehicles with direct fuel injection systems, particularly in models with known injector issues.
Moderate – It is advisable to address this issue soon to prevent further engine performance problems.
Driving with a malfunctioning fuel injection system can lead to increased emissions and potential engine damage.
• Engine at operating temperature
• Vehicle at idle
The fuel injector for cylinder 2 is located on the engine's cylinder head, typically accessible from the top of the engine.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to poor fuel economy, increased emissions, and potential engine damage.
Q: Can I drive my car with this code?
A: While the car may still be drivable, it is recommended to have it checked by a mechanic to avoid further issues.
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