DTC Code P1349 – What does this code mean for BMW?

<ul> <li><b>Engine Light ON (or Service Engine Soon Warning Light)</b>: The illumination of the engine light indicates a detected issue with cylinder 4 misfiring. This is often the first noticeable symptom.</li> <li><b>Rough Engine Idle</b>: A misfire in cylinder 4 can cause the engine to idle roughly, leading to vibrations and an unstable idle speed.</li> <li><b>Reduced Engine Performance</b>: The misfire can result in a noticeable drop in engine power and performance, affecting acceleration and overall drivability.</li> <li><b>Increased Fuel Consumption</b>: Due to the misfire, the engine may consume more fuel than usual as it attempts to compensate for the loss of power.</li> <li><b>Possible Engine Stalling</b>: In severe cases, the misfire can cause the engine to stall, especially at low speeds or when idling.</li> </ul>

<ul><li>Faulty spark plug can cause misfires due to improper ignition in cylinder 4.</li><li>Faulty ignition coil may lead to insufficient spark generation, resulting in misfires.</li><li>An intake vacuum leak can disrupt the air-fuel mixture, causing misfires.</li><li>A faulty camshaft position sensor can lead to incorrect timing, affecting cylinder 4's performance.</li><li>An open or shorted ignition coil harness can interrupt the electrical flow, causing misfires.</li><li>Poor electrical connection in the ignition coil circuit can lead to intermittent misfires in cylinder 4.</li></ul>

<ul> <li><b>Initial Scan</b>: Use an OBD-II scanner to confirm the presence of DTC P1349 and check for any additional codes.</li> <li><b>Visual Inspection</b>: Inspect the ignition coil, spark plug, and wiring for cylinder 4 for any visible damage or wear.</li> <li><b>Ignition Coil Test</b>: Swap the ignition coil from cylinder 4 with another cylinder. Clear the codes and see if the misfire follows the coil.</li> <li><b>Spark Plug Inspection</b>: Remove and inspect the spark plug from cylinder 4. Check for fouling, wear, or improper gap. Replace if necessary.</li> <li><b>Fuel Injector Test</b>: Check the fuel injector for cylinder 4. Listen for injector operation using a mechanic's stethoscope. Swap injectors if necessary to see if the misfire follows.</li> <li><b>Compression Test</b>: Perform a compression test on cylinder 4 to ensure there are no mechanical issues such as a burnt valve or piston ring failure.</li> <li><b>ECU and Wiring Check</b>: Inspect the ECU and related wiring for any signs of damage or corrosion. Ensure proper connections and continuity.</li> <li><b>Final Verification</b>: After addressing any identified issues, clear the codes and perform a road test to ensure the problem is resolved.</li></ul>

<p>The DTC code P1349 indicates a misfire in cylinder 4 with fuel cut-off in BMW vehicles. This is a <b>critical</b> issue that can lead to severe engine damage if not addressed immediately. Potential causes include faulty spark plugs, ignition coils, or fuel injectors. Immediate action is required to prevent further damage and ensure safe vehicle operation.</p>