Skoda Praktik check engine light and fuel consumption

Sounds like a VANOS issue. I had a similar problem with my old BMW. Check engine light, low power, and drinking fuel like it was going out of style. The VANOS solenoid is a common culprit, especially with that mileage. Have you scanned the OBD2 for specific codes? It could also be a variable timing issue or a stretched timing chain, but start with the solenoid. Is there power available to the solenoid?

Thanks for the quick reply! I did a scan, and it pointed to the inlet VANOS mechanics being faulty. I suspect a defect in one of the camshaft solenoid valves or power supply not available. How did you pinpoint the solenoid on your BMW?

The OBD code should point you in the right direction. In my case, the BMW-specific code was related to VANOS performance on one of the banks. I then tested the solenoid by swapping it with another one (if your engine allows that), and the problem followed the solenoid. If you're not comfortable with that, or if the power supply is the issue, I'd advise taking it to a trusted workshop. Diagnosing variable timing issues can be tricky without the right tools and knowledge. A stretched timing chain can cause similar issues, but that's less common.

Thank you for confirming my suspicions and for the detailed insights. I took it to a workshop, and you were spot on: faulty VANOS solenoid. Replaced it, and the check engine light is gone, and fuel consumption is back to normal. Cost me around 250€, as expected.