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 car's alternative fuel pump. It's like a helper pump that isn't working right because the computer is getting a signal that's too high.
The engine control module (ECM) has detected a high voltage signal from the alternative fuel pump B compression stroke valve control circuit.
The P2A86 code indicates that the ECM has received a signal from the alternative fuel pump B compression stroke valve control circuit that is higher than expected. This could be due to a malfunctioning component or an electrical issue in the circuit.
• Check Engine Light is on
• Reduced engine performance
• Possible fuel efficiency issues
• Faulty alternative fuel pump
• Damaged wiring or connectors
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the alternative fuel pump for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty alternative fuel pump.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Vehicle 1
• Vehicle 2
• Vehicle 3
• Regular maintenance checks
• Ensure proper fuel quality
• Inspect electrical connections periodically
Engine Performance
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional.
• Avoid driving the vehicle if performance is severely affected.
Check with your vehicle manufacturer for warranty coverage on fuel system components.
This code is relatively uncommon and typically associated with vehicles using alternative fuel systems.
Moderate – Should be addressed soon to prevent further engine performance issues.
Driving with a malfunctioning fuel system can lead to reduced performance and increased emissions.
• Engine running
• Vehicle at operating temperature
The alternative fuel pump is typically located near the fuel tank or along the fuel line.
Q: Can I drive with a P2A86 code?
A: It's not recommended to drive for long periods with this code as it can affect engine performance.
Q: What happens if I ignore the P2A86 code?
A: Ignoring the code can lead to further engine performance issues and potential damage to the fuel system.
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