This article addresses troubleshooting a 2005 VW 1.9L TDI BEW engine using VCDS, specifically focusing on the camshaft position sensor and its associated measuring blocks. The vehicle exhibits symptoms like intermittent starting issues, black smoke on startup, occasional hesitation, and an immediate check engine light upon clearing fault codes. A VCDS scan reveals several fault codes, including one for the camshaft position sensor (G40).
Understanding the Fault Codes
A VCDS scan revealed the following engine-related fault codes:
- 16725 – Camshaft Position Sensor (G40) P0341 – 000 – Implausible Signal – Intermittent: This code directly implicates the camshaft position sensor (G40) and suggests an inconsistent signal. This can lead to timing issues, affecting starting and performance.
- 18996 – Turbocharger Boost Control Position Sensor Circuit P2564 – 000 – Signal too Low: This code points to a problem with the turbocharger boost control system. It often relates to vacuum leaks, which can also cause hesitation.
- 16485 – Mass Air Flow Sensor (G70) P0101 – 000 – Implausible Signal: This code indicates a problem with the MAF sensor reading, potentially caused by vacuum leaks or a faulty sensor.
Additionally, a “Company Data Bus for Comfort System” fault was found across multiple modules. This will be addressed separately.
Investigating the Camshaft Position Sensor with VCDS
While the Ross-Tech Wiki recommends checking Measuring Block 043.2 for the boost pressure sensor (G500) in 2.0L PD TDI engines (BRM and BEW), this specific engine is a 1.9L BEW. For the 1.9L BEW, the relevant measuring blocks for the camshaft position sensor (G40) are typically found within Group 004.
Accessing Measuring Block 004:
- Connect your VCDS interface to the vehicle’s OBD-II port.
- Turn the ignition on.
- Launch the VCDS software.
- Select “Select Control Module”.
- Choose “01 – Engine”.
- Select “Measuring Blocks – 08”.
- Enter “004” in the “Group” field and click “Go!”.
Interpreting Measuring Block 004:
This block often displays values related to engine speed, engine load, and importantly, synchronization between the crankshaft and camshaft. Look for fields indicating “Syncro Angle” or similar. A significant deviation from the expected value (usually 0 degrees or a specific tolerance range) signifies a problem with the camshaft position sensor or timing belt.
Addressing Other Fault Codes
- Vacuum Leak: Inspect the intercooler piping, vacuum hoses, and related components for leaks. A thorough visual inspection, along with a smoke test, can pinpoint leaks effectively.
- MAF Sensor: While already replaced, a confirmed vacuum leak can cause implausible MAF readings. Address the vacuum leak first before further diagnosing the MAF.
- Company Data Bus for Comfort System: This likely indicates a communication issue between modules. Check the wiring and connectors associated with the comfort system modules for damage or corrosion.
Conclusion
Troubleshooting a P0341 fault code on a 1.9L BEW engine requires systematic diagnosis. Utilize VCDS to monitor Measuring Block 004 for camshaft/crankshaft synchronization. Address the vacuum leak and re-evaluate the MAF sensor afterward. The “Company Data Bus” issue warrants further investigation into the comfort system’s wiring. Resolving these issues should restore the engine to proper running condition.
