Fault code P008B is called “Low Pressure Fuel System Pressure – Too High” but in different programs it may be called differently. This fault designation applies to all vehicles equipped with OBD-II.
Technical description and explained code P008B
This Diagnostic Trouble Code (DTC) is a generic powertrain code. Error P008B is considered a general code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly depending on the model.
Low-pressure systems are used in diesel vehicles to supply fuel to the high-pressure fuel pump. The fuel injection pump does the job of providing diesel engines with the high fuel pressure necessary for quality atomization.
The fuel passes through numerous filters, pumps, injectors, lines and connections to eventually reach the engine. The proper condition of the entire fuel system must be monitored for proper operation.
It is very important that the engine control module (ECM) clearly monitors these conditions as well. Any air ingress caused by an inoperative pump or injector under load can cause serious problems.
In addition to keeping the fuel system in proper condition, attention must be paid to the quality of the fuel being filled. As it can cause contamination not only of the fuel tank, but also of the fuel pump and the entire fuel system.
Code P008B is set when the ECM module detects high pressure in the low fuel pressure system.
Symptoms of vehicle malfunctions
The main signal that an error P008B has occurred is the Malfunction Indicator Lamp (MIL) is also known as the CheckEngine Light.
It can also be warning signs such as:
- The “Check engine” control lamp on the control panel will illuminate (the code will be stored as a fault).
- Other related fault codes may also be present, e.g. ignition misfire.
- Decreased engine power.
- The engine cannot be accelerated and throttle response is unresponsive.
- Increased smokiness from the exhaust pipe when starting.
- The engine may fail the emissions test.
- Increased fuel consumption.
- Engine noise during operation.
- Difficulty in starting the engine.
The severity of error P008B is moderate to high, and the cause should be corrected as soon as possible. It can lead to serious mechanical damage in the future.
Factors that can cause this error code
The error code P008B can mean that one or more of the following problems have occurred:
- Use of contaminated fuel.
- Fuel of improper quality.
- Problem with fuel line or filter.
- Faulty fuel injectors.
- Faulty low-pressure fuel pump.
How to fix or reset OBD-2 code P008B
Some suggested steps for troubleshooting and fix the error code P008B:
- Read all stored data and error codes with an OBD-II scan tool.
- Clear the error codes from the computer memory.
- Test-drive the vehicle to find out if error P008B appears again.
- Check the quality of the fuel used.
- Visually inspect the fuel line as well as the fuel filter, it may need to be replaced.
- Check the fuel injectors to make sure they are in proper condition.
- Test the low-pressure fuel pump.
Diagnose and repair of problems
Before diagnosing code P008B, make sure there are no leaks in the system, and if there are, repair them. Leaks can result in low fuel pressure in any closed system.
Rusty lines, fuel filter gaskets, worn o-rings can cause fuel leaks.
Check the low fuel pressure system filter, it may be located on the frame or near the fuel tank. From its appearance, you should be able to tell if the fuel filter has been replaced recently or if it has never been changed.
Locate the fuel injector, making sure no connections or connectors are leaking fuel. Leaks are often found around the o-ring itself, visually check for signs of physical damage.
It is not unreasonable to check the quality of the fuel you fill your car with, in some cases this is the cause.
If after the tests the error code P008B persists, you need to test the low pressure fuel pump. It may have a malfunction that affects the fuel pressure in the low pressure system.
On which vehicles does this problem occur most frequently
Fault code P008B can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- Audi (A4)
- Dodge
- Ford (Fiesta, Fusion)
- Hyundai
- Land Rover (Range Rover)
- Mazda
- Mercedes-Benz
- Peugeot (3008, 308)
- MAZ
Fault code P008B can sometimes be found with other errors. The most common are the following: P008A, P00B9, P00BA, P2539, P2540, P2541, P2542, P2543.
