P0091 2018 GMC Sierra Code - Fuel Pressure Regulator Control Circuit Low Voltage
Quick Answer
The P0091 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates a problem with the fuel pressure regulator control circuit experiencing low voltage. Common causes include Faulty fuel pressure regulator, Damaged wiring or connectors in the control circuit, Malfunctioning fuel pump. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P0091 2018 GMC Sierra indicates Fuel Pressure Regulator Control Circuit Low Voltage.
- Common causes
- Common causes include Faulty fuel pressure regulator, Damaged wiring or connectors in the control circuit, Malfunctioning fuel pump.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code P0091 2018 GMC Sierra Description
The P0091 diagnostic trouble code (DTC) for a 2018 GMC Sierra indicates a problem with the fuel pressure regulator control circuit experiencing low voltage. The fuel pressure regulator is a crucial component in the vehicle's fuel system, responsible for maintaining the correct fuel pressure to ensure proper engine performance and efficiency. When the control circuit of the fuel pressure regulator detects low voltage, it can lead to a variety of issues that can affect the vehicle's overall performance.
Common Causes of P0091 2018 GMC Sierra
- Faulty fuel pressure regulator
- Damaged wiring or connectors in the control circuit
- Malfunctioning fuel pump
- Issues with the powertrain control module (PCM)
- Electrical issues such as a blown fuse or relay
Symptoms of P0091 2018 GMC Sierra
- Check engine light illuminated on the dashboard
- Engine misfires or hesitation during acceleration
- Rough idling or stalling
- Decreased fuel efficiency
- Difficulty starting the vehicle
How to Fix P0091 2018 GMC Sierra
- Begin by conducting a visual inspection of the wiring and connectors in the fuel pressure regulator control circuit to check for any visible damage or corrosion.
- Use a multimeter to test the voltage at the fuel pressure regulator to determine if it is within the specified range. If the voltage is low, the fuel pressure regulator may need to be replaced.
- Inspect the fuel pump to ensure it is functioning correctly and providing adequate fuel pressure to the engine.
- Check the powertrain control module (PCM) for any error codes related to the fuel pressure regulator control circuit and perform any necessary repairs or reprogramming.
- Clear the diagnostic trouble codes from the vehicle's computer and test drive the vehicle to ensure the issue has been resolved.
Cost to Fix P0091 2018 GMC Sierra
The typical repair costs for addressing a P0091 code on a 2018 GMC Sierra can vary depending on the specific cause of the issue. In general, replacing a faulty fuel pressure regulator can cost between $150 and $300, while addressing wiring or connector issues may range from $100 to $200. If the fuel pump needs to be replaced, the cost can be higher, typically ranging from $300 to $600. Labor costs at auto repair shops can vary, with hourly rates typically between $80 and $150. It's recommended to consult with a certified mechanic or dealership for a more accurate estimate based on the specific circumstances of the vehicle.
Need more information about the P0091 2018 GMC Sierra code?
Need more information on how to fix the P0091 2018 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the P0091 2018 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about P0091 2018 GMC Sierra Code
What does the OBDII code P0091 mean for a 2018 GMC Sierra?
P0091 indicates "Fuel Pressure Regulator Control Circuit Low Voltage," meaning the vehicle's ECM has detected an issue with the electrical signal controlling the fuel pressure regulator.
What are the symptoms of code P0091 in a 2018 GMC Sierra?
Common symptoms include difficulty starting, poor engine performance, reduced fuel efficiency, and possible stalling.
What causes code P0091 in a 2018 GMC Sierra?
Potential causes include a faulty fuel pressure regulator, damaged wiring or connectors in the control circuit, or a failing ECM.
Can I drive my 2018 GMC Sierra with a P0091 code?
Driving with this code is not recommended, as it can lead to poor engine performance, stalling, or further damage to the fuel system.
How is code P0091 diagnosed on a 2018 GMC Sierra?
A mechanic typically uses a scan tool to confirm the code, inspects the wiring and connectors, tests the fuel pressure regulator, and checks the ECM for issues.
What repairs can fix code P0091 in a 2018 GMC Sierra?
Repairs may involve replacing the fuel pressure regulator, repairing or replacing damaged wiring/connectors, or reprogramming or replacing the ECM.
How much does it cost to fix P0091 on a 2018 GMC Sierra?
Repair costs vary, but replacing a fuel pressure regulator typically ranges between $150 and $400, while ECM-related repairs could be more expensive.
Can a bad fuel pump cause code P0091 in a 2018 GMC Sierra?
While unlikely, a failing fuel pump could indirectly contribute to the code if it causes irregular fuel pressure that affects the regulator's operation.
How can I prevent code P0091 in my 2018 GMC Sierra?
Regular maintenance, inspecting wiring for damage, and using clean fuel can help prevent issues related to the fuel pressure regulator circuit.
Will resetting the code clear P0091 on my 2018 GMC Sierra?
Resetting the code might temporarily clear it, but the underlying issue must be fixed to prevent the code from returning.
Discuss the causes and fixes for P0091 2018 GMC Sierra OBDII Code
Code P0091 2018 GMC Sierra comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.