Fault code P2291 is called “Injector Control Pressure Too Low – Engine Cranking” 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 P2291
This Diagnostic Trouble Code (DTC) is a generic powertrain code. Error P2291 is considered a general code because it applies to all makes and models of vehicles. Although the specific repair steps may vary slightly from model to model.
Saving this code means that the powertrain control module (PCM) has detected insufficient pressure. Required to control the high pressure fuel injection system, when starting the engine.
Although this code is used primarily in diesel high pressure fuel injection systems, it can also be used in vehicles with gasoline engines. The PCM controls high-pressure fuel injection using one or more fuel pressure sensors.
The high-pressure injection system of a diesel engine operates on the valve timing and is driven by the main components of the engine timing. Incorrect pressure in the injector control system can indicate a serious malfunction in the engine’s lubrication or timing mechanisms.
The conditions that cause this code to appear may be due to either mechanical or electrical causes.
If the PCM detects insufficient injector control pressure, code P2291 will be stored and the Malfunction Indicator Light (MIL) will illuminate. It may take several ignition failure cycles to illuminate.
Symptoms of vehicle malfunctions
The main signal that an error P2291 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 light up (the code will be stored as a fault).
- Other related trouble codes may also be present.
- Excessive amount of smoke from the exhaust pipe.
- Abnormal noises from the engine compartment.
- The engine may not start.
In most cases, the error P2291 is high, as it can lead to serious consequences for the engine. Therefore, it is recommended to eliminate its causes as soon as possible.
Factors that can cause this error code
The error code P2291 can mean that one or more of the following problems have occurred:
- High pressure injection pressure switch is defective.
- Injection pressure sensor has failed.
- Open or short circuit in control circuit.
- Low oil level.
- Low oil pressure.
- Sometimes the cause is faulty PCM module.
How to fix or reset OBD-2 code P2291
Some suggested steps for troubleshooting and fix the error code P2291:
- Connect the OBD-II scanner to the vehicle’s diagnostic connector and read all stored data and error codes.
- Before continuing with diagnosis code P2291, check the oil level.
- If the level is normal, check the oil pressure.
- Also check the hoses for leaks.
- Inspect and test the associated wiring.
- If necessary, repair or replace any wires that are shorted, broken, damaged, or corroded.
- Test the injection pressure sensor as well as the relay.
Diagnose and repair of problems
Before diagnosing error P2291, check that the engine is filled with oil to the proper level and that the oil pressure and oil level lamps on the instrument panel are not illuminated. If not, it may be necessary to check the oil pressure manually.
Oil pressure affects the timing components of the engine. High pressure injection is driven by engine timing components. If the oil pressure in the engine is low, the injection phasing can be adversely affected.
Next, make a visual inspection of the associated wiring harnesses as well as the connectors. Repair or replace wiring that has been cut, burned, or otherwise damaged.
Checking the electrical part
Using a multimeter, check the voltage and ground circuits on the injection system pressure sensor. If no voltage is detected, check the system fuses, replacing the blown ones if necessary.
If voltage is detected, check the corresponding circuit on the PCM connector. If no voltage is detected, there is likely an open circuit between this sensor and the PCM. If voltage is detected on the PCM, the module itself may be defective or there may be a programming error.
Also, when troubleshooting error P2291, the injection pressure sensor itself should be checked with a multimeter. If it does not meet the manufacturer’s specifications, then it is defective and must be replaced.
On which vehicles does this problem occur most frequently
Fault code P2291 can occur on different vehicles but there are statistics on which brands this occurs most often. Here is a list of some of them:
- BMW
- Citroen (C4, Jumper)
- Ford (Connect, F-250, Mondeo, Ranger, Tourneo, Transit)
- Land Rover (Range Rover)
- Peugeot (3008, 4007, 508, Boxer, Partner)
- Volvo
Fault code P2291 can sometimes be found with other errors. The most common are the following: P2283, P2284, P2285, P2286, P2287, P2288, P2289, P2290, P2292, P2623, P2624, P2625.
