<ul> <li><b>Engine Light ON (or Service Engine Soon Warning Light)</b>: The illumination of the engine light indicates that the vehicle's onboard diagnostics system has detected an issue with the fuel pressure regulator. This could be due to the fuel pressure regulator 2 exceeding learning limits and being too low.</li> <li><b>Poor Engine Performance</b>: The engine may exhibit poor performance, including rough idling, stalling, or hesitation during acceleration. This is often caused by inadequate fuel pressure due to the malfunctioning fuel pressure regulator.</li> <li><b>Reduced Fuel Efficiency</b>: A drop in fuel efficiency can occur as the engine compensates for the incorrect fuel pressure, leading to increased fuel consumption.</li> <li><b>Difficulty Starting the Engine</b>: The vehicle may have trouble starting, especially in cold conditions, due to insufficient fuel pressure reaching the engine.</li> </ul>

<ul><li>The fuel pressure regulator may be malfunctioning, causing incorrect fuel pressure readings.</li><li>A defective fuel pump can lead to insufficient fuel delivery, resulting in low fuel pressure.</li><li>The fuel pressure sensor might be providing inaccurate data, leading to erroneous fuel pressure regulation.</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 this 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. If no voltage is detected, check system fuses and replace if necessary.</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 the fuel pressure sensor. If either component does not meet manufacturer's specifications, consider it defective.</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 in the fuel rail.</li></ul>

<p>The DTC code P229C indicates that the Fuel Pressure Regulator 2 has exceeded learning limits and is too low. This is a critical issue.</p><ul><li><b>Immediate Actions:</b> Inspect and possibly replace the fuel pressure regulator.</li><li><b>Potential Risks:</b> Delayed repair can lead to engine misfires, poor fuel economy, and potential engine damage.</li></ul>