<ul> <li><b>Engine Light ON (or Service Engine Soon Warning Light)</b>: The illumination of the engine light indicates that the ECU has detected an issue with the fuel pressure regulator. This could be due to the fuel pressure regulator 2 exceeding its learning limits and being too high.</li> <li><b>Poor Engine Performance</b>: The vehicle may experience poor engine performance, such as rough idling, hesitation, or stalling. This is often caused by incorrect fuel pressure regulation.</li> <li><b>Reduced Fuel Efficiency</b>: A malfunctioning fuel pressure regulator can lead to improper fuel delivery, resulting in reduced fuel efficiency.</li> <li><b>Difficulty Starting the Engine</b>: The engine may have difficulty starting due to incorrect fuel pressure, which can be a direct result of the fuel pressure regulator exceeding its learning limits.</li> </ul>

<ul><li>The fuel pressure regulator may be malfunctioning, causing it to exceed the learning limits.</li><li>A defective fuel pump can lead to excessive fuel pressure, triggering the error code.</li><li>The fuel pressure sensor might be providing incorrect readings, resulting in the system detecting higher than normal pressure.</li></ul>

<ul> <li><b>Retrieve Codes and Freeze Frame Data</b>: Connect the diagnostic scanner to the vehicle's diagnostic port. Retrieve all stored codes and pertinent freeze frame data. Write down the information for reference.</li> <li><b>Clear Codes and Test Drive</b>: Clear the codes and test drive the vehicle until the code is restored or the PCM enters readiness mode. If the code is intermittent, the condition may need to worsen for accurate diagnosis.</li> <li><b>Perform Visual Inspection</b>: Inspect related wiring and connectors for damage. Repair or replace any cut, burned, or damaged wiring.</li> <li><b>Test Voltage and Ground Circuits</b>: Use a DVOM to test voltage and ground circuits at the electronic fuel regulator (2) and fuel pressure sensor/s. Check system fuses if no voltage is detected.</li> <li><b>Check PCM Connector</b>: Test the corresponding circuit at the PCM connector. If no voltage is detected, suspect an open circuit between the sensor and the PCM. If voltage is present, suspect a defective PCM or PCM programming error.</li> <li><b>Test Fuel Pressure Regulator and Sensor</b>: Use the DVOM to test the fuel pressure regulator and fuel pressure sensor. Replace any components that do not meet manufacturer's specifications.</li> <li><b>Manual Fuel Pressure Test</b>: Use a manual fuel pressure gauge to test actual fuel pressure at the rail. Perform this test with the ignition switch in the key on engine off (KOEO) position. Exercise caution due to high pressure.</li></ul>

<p>The DTC code P229D indicates that the Fuel Pressure Regulator 2 has exceeded its learning limits and is too high. This is a critical issue.</p><ul><li><b>Immediate Actions:</b> Inspect and possibly replace the fuel pressure regulator.</li><li>Check for any fuel system leaks or blockages.</li><li>Verify the fuel pump operation and fuel filter condition.</li></ul><p>Delaying repair can lead to severe engine performance issues, potential engine damage, and unsafe driving conditions.</p>