29CE

What the Code Means

Code 29CE indicates a misfire in cylinder 2 of the N54 engine. A misfire occurs when the fuel-air mixture in the cylinder doesn't ignite properly. It can be caused by a faulty ignition system (coil, spark plug), fuel system (fuel injector), or mechanical problems. Diagnosis and causes are the same as for cylinder 1 misfire codes.

Symptoms

• Engine: rough idle, power loss, hesitation under load
• Indicators: Check Engine Light (CEL) comes on

Diagnosis and Repair

Step 1: Read the Codes

Use ISTA or INPA to confirm the code and check for related faults.

Step 2: Check the Ignition Coil

Swap the ignition coil from cylinder 2 to cylinder 1. If the misfire moves to cylinder 1, replace the coil (original part number 12138616153).

Step 3: Check the Spark Plug

If the misfire stays on cylinder 2, swap the spark plug from cylinder 2 to cylinder 1. If the misfire moves, replace all plugs (NGK original 97506).

Step 4: Check the Injector

If the misfire persists, check the cylinder 2 fuel injector for leaks or clogging. Replace the fuel injector if needed (original part number 13537585261-12).

Step 5: Adaptation and Test Drive

After the repair, clear the codes and reset adaptations. Take a test drive to verify.

Secondary Damage

Ignoring the fault can lead to:

• Catalytic converter damage from unburned fuel
• A severe misfire can also damage the engine (e.g., hydrolock or overheating)