P0091 GMC Code - Fuel Pressure Regulator Control Circuit Low Voltage
Quick Answer
High-pressure fuel is regulated by the high-pressure fuel pump actuator, which is a part of the high-pressure fuel pump. Common causes include Faulty High-Pressure Fuel Pump, High-Pressure Fuel Pump harness is open or shorted, High-Pressure Fuel Pump electrical circuit poor connection. 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 GMC indicates Fuel Pressure Regulator Control Circuit Low Voltage.
- Common causes
- Common causes include Faulty High-Pressure Fuel Pump, High-Pressure Fuel Pump harness is open or shorted, High-Pressure Fuel Pump electrical circuit poor connection.
- 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.
Code P0091 GMC Description
What are the Possible Causes of the DTC P0091 GMC?
- Faulty High-Pressure Fuel Pump
- High-Pressure Fuel Pump harness is open or shorted
- High-Pressure Fuel Pump electrical circuit poor connection
- Faulty Engine Control Module (ECM)
How to Fix the DTC P0091 GMC?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0091 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P0091 GMC code?
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Information for Specific GMC Models
- P0091 2014 GMC Sierra — Fuel Pressure Regulator Control Circuit Low Voltage
- P0091 2015 GMC Sierra — Fuel Pressure Regulator Control Circuit Low Voltage
- P0091 2016 GMC Sierra — Fuel Pressure Regulator Control Circuit Low Voltage
- P0091 2017 GMC Sierra — Fuel Pressure Regulator Control Circuit Low Voltage
- P0091 2018 GMC Sierra — Fuel Pressure Regulator Control Circuit Low Voltage
Frequently Asked Questions about P0091 GMC Code
1. What does the OBDII code P0091 mean for a GMC vehicle?
P0091 indicates that the Engine Control Module (ECM) has detected a low voltage issue in the fuel pressure regulator control circuit.
2. What are the common symptoms of code P0091 in a GMC?
Symptoms may include difficulty starting the engine, rough idling, reduced fuel efficiency, loss of power, or the Check Engine Light illuminating.
3. What causes the P0091 code to appear in GMC vehicles?
Common causes include a faulty fuel pressure regulator, damaged wiring or connectors in the circuit, a defective ECM, or low fuel pressure due to a failing fuel pump.
4. Can a dirty fuel filter trigger code P0091 in a GMC?
While a dirty fuel filter can restrict fuel flow, it is not a direct cause of P0091. However, it may contribute to low fuel pressure, which could be misdiagnosed.
5. How do you diagnose code P0091 on a GMC?
Diagnosis typically involves inspecting the fuel pressure regulator, checking wiring and connectors for damage, testing the voltage and resistance in the control circuit, and verifying fuel pressure.
6. Is it safe to drive a GMC with the P0091 code?
Driving with a P0091 code is not recommended, as it can lead to poor performance, increased emissions, and potential engine damage if the issue is not addressed.
7. What tools are needed to troubleshoot P0091 in a GMC?
You will need an OBDII scanner, a multimeter, and possibly a fuel pressure gauge to diagnose the issue accurately.
8. How much does it cost to repair the P0091 code on a GMC?
Repair costs vary depending on the issue, ranging from $100-$300 for wiring or connector repairs to $400-$800 if the fuel pressure regulator or fuel pump needs replacement.
9. Can a weak battery cause the P0091 code in a GMC?
A weak battery could potentially cause low voltage issues in the fuel pressure regulator circuit, so it’s worth testing the battery and charging system.
10. How do you prevent the P0091 code from occurring in a GMC?
Regular maintenance, such as inspecting wiring, connectors, and the fuel system components, can help prevent issues leading to the P0091 code.
Discuss the causes and fixes for P0091 GMC OBDII Code
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