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 reading the pressure from a sensor that helps control fuel flow in cars that use alternative fuels. It's like when a video game controller keeps disconnecting and reconnecting while you're playing.
The P2A79 code indicates an issue with the signal from the hydraulic pump pressure sensor, which is critical in managing the pressure for alternative fuel systems.
The P2A79 code is triggered when the Engine Control Module (ECM) detects an intermittent or erratic signal from the hydraulic pump pressure sensor. This sensor is responsible for monitoring the pressure levels in the hydraulic system of vehicles that use alternative fuels. An erratic signal can lead to improper fuel pressure regulation, affecting engine performance.
• Check Engine Light is on
• Poor fuel efficiency
• Engine performance issues
• Faulty hydraulic pump pressure sensor
• Damaged or corroded wiring/connectors
• ECM software issue
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage or corrosion
• Test the hydraulic pump pressure sensor for proper operation
• Replace the faulty hydraulic pump pressure sensor
• Repair or replace damaged wiring/connectors
• Update ECM software if necessary
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks
• Keep connectors clean and free of corrosion
• Ensure software updates are applied promptly
Sensor Issue
• Do not ignore the Check Engine Light
• Seek professional diagnostic services
• Consider regular vehicle inspections
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code is relatively uncommon and typically associated with vehicles that use alternative fuels.
Moderate – While the vehicle may still operate, ignoring this issue can lead to decreased performance and fuel efficiency.
Driving with a malfunctioning fuel system sensor can lead to increased emissions and may not comply with emissions regulations.
• Engine running
• Vehicle at operating temperature
The hydraulic pump pressure sensor is typically located near the fuel tank or along the fuel line in vehicles with alternative fuel systems.
Q: Can I drive my car with the P2A79 code?
A: While you can drive the car, it's not recommended as it may lead to poor performance and fuel efficiency.
Q: How can I prevent this code from appearing again?
A: Regular maintenance and ensuring all connectors are clean and secure can help prevent this issue.
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