P1187 - FAULT CODE - OBD2

P1187 HYUNDAI, KIA:  FUEL PRESSURE MONITORING - REGULATOR VALVE STICK

The function of the fuel system of vehicles with internal combustion engines is to supply the necessary amount of fuel to the engine, in order to achieve the best performance of the engine. There are many components that make up this system, among which the fuel tank, lines, filters, fuel pump and a regulator stand out.

Fuel pressure monitoring is used to look for problems and leaks in the high-pressure system. The Engine Control Module (ECM) determines the rail pressure value based on engine operating conditions. It also controls the fuel pressure regulator, which ensures that the rail pressure reaches a required value.

The fuel line pressure, which includes the injectors and pumps, is continuously monitored during engine operation. In case the system monitoring generates a threshold value, the ECM will interpret it as a fault and set the DTC P1187 OBDII code.

• Check Engine lamp illuminates.
• Engine operation disabled.

The P1187 OBD2 diagnostic code is stored for one of the following reasons:

• The fuel pressure regulator may have damage.
• The Fuel Rail Pressure Sensor may be in poor condition.
• The Engine Control Module (ECM) could be faulty.

The corresponding steps to resolve the P1187 OBDII fault code are:

• Consult the Technical Service Bulletins.
• Using a scan tool it is necessary to check if additional DTCs to P1187 are stored, paying attention to those that refer to specific fuel system component failures. If so, perform the diagnosis of those codes first.
• Check the fuel pressure regulator for damage. If you discover deficiencies on the fuel pressure regulator, make the necessary corrections.
• Check the Fuel Rail Pressure Sensor for proper operation, if you determine that it is damaged, consider replacing it.