my Porsche Cayenne E3 (2018-Present) has a check engine light and the code is P0303, what does it me...

Learn how to diagnose and fix P0303 cylinder 3 misfire in Porsche Cayenne E3. Step-by-step guide with diagnostic procedures and repair instructions.

Solution

1. Preparation

• Gather necessary tools and parts.
• Disconnect the negative battery terminal to ensure safety during repairs.

2. Inspect and Replace Ignition Components

• Tools Required: Socket set, torque wrench, spark plug socket, ignition coil puller.
• Remove the engine cover if applicable.
• Locate the ignition coil for cylinder 3 (refer to user manual for exact location).
• Remove the ignition coil by unscrewing its retaining bolts and disconnecting the electrical connector.
• Inspect the spark plug condition; if worn or fouled, replace it.
• Install the new spark plug and torque it to manufacturer specifications (typically around 15-20 lb-ft).
• Reinstall the ignition coil and reconnect the electrical connector.

3. Check Fuel Injector

• Tools Required: Fuel injector cleaning kit or noid light.
• Disconnect the fuel injector connector for cylinder 3.
• Use a noid light to check for signal at the connector; if no signal is present, further diagnose the wiring and ECM.
• If the injector is faulty, remove it using an injector puller and replace it with a new one.
• Reconnect the fuel injector connector.

4. Perform Compression Test

• Tools Required: Compression tester.
• Remove the spark plug from cylinder 3.
• Insert the compression tester into the spark plug hole.
• Crank the engine and record the compression reading. Compare it to manufacturer specifications (usually around 120-170 psi).
• If the compression is low, further investigate potential issues with piston rings or valves.

5. Reassembly and Final Check

• Reinstall any components removed during the process (engine cover, connectors).
• Reconnect the negative battery terminal.
• Clear the DTC using the OBD-II scanner.