P0091 OBD-II: Fuel Pressure Regulator 1 Control Circuit Low
P0091 Severity
Will P0091 go away on its own?
Once the vehicle's onboard system no longer detects the issue, most codes will disappear on their own. If your vehicle still has this code, however, it should be properly diagnosed to avoid a more serious problem.
For a proper diagnosis, RepairPal Certified shops have the equipment, tools, and expertise.
Moderate severity codes might not threaten the vehicle's safety or functionality immediately, but you should still get it diagnosed within a reasonable time frame to keep your car running well.
What causes OBD-II fault code P0091?
Diesel engines operate off of high fuel pressure. The engine computer (PCM) uses a Fuel Pressure Regulator to control the fuel on the low pressure side (from the fuel tank) to the high pressure injection pump (pressurizes the fuel to the injectors). If the PCM cannot control the fuel pressure regulator, code P0091 will set.
OBD II Fault Code
- OBD II P0091
OBD-II Code Decreased engine performance is defined as a Fuel Pressure Regulator 1 Control Circuit Low
Diesel engines operate off of high fuel pressure. The engine computer (PCM) uses a Fuel Pressure Regulator to control the fuel on the low pressure side (from the fuel tank) to the high pressure injection pump (pressurizes the fuel to the injectors). If the PCM cannot control the fuel pressure regulator, code P0091 will set.
Decreased engine performance Symptoms
- Decreased engine performance
- Increased fuel consumption
Common Problems That Trigger the P0091 Code
- Fuel pressure regulator failure
- Powertrain Control Module (PCM) failure
- Wiring issue
Ask our experts about P0091.
RepairPal Car Genius™ is a free resource for vehicle owners seeking advice on maintenance, auto repair, shop inquiries, estimates, and finding a trustworthy repair shop in your area.
Call us at 877-913-1554
Available 9am – 6pm ET Monday through Friday
