VW Bora Owner Reports VANOS Issues and Fuel Problems

I dealt with similar issues on my 2003 VW Golf 1.8T. Based on some experience working on VWs, variable timing problems can be tricky to diagnose correctly. My car showed almost identical symptoms, illuminated check engine light and increased fuel consumption. The workshop found a faulty camshaft solenoid that was causing timing issues. The repair involved replacing the VANOS solenoid and cleaning out some oil sludge that had built up in the system. Total cost was 250€ and the repair took about 4 hours. The symptoms improved immediately after the fix, fuel economy returned to normal and the check engine light stayed off. Regular oil changes are crucial to prevent VANOS failure and similar issues from recurring. To help diagnose your specific case, could you share: Current mileage, Last oil change date, Any unusual engine sounds, Specific error codes from the check engine light, Oil type currently being used This information would help determine if your issue is similar to what I experienced or if there might be other factors involved with the variable timing system.

Last service was done at 69000km and I am now at 71737km. The timing issue seems similar but I am getting some occasional rough idle that was not mentioned in your description. Will get the error codes read and update. Thanks for the detailed response regarding the VANOS solenoid replacement and oil sludge cleaning. Based on your repair time estimate, I will plan accordingly for the potential downtime.

Thanks for providing those additional details. The rough idle you mentioned actually reminds me of how my VW Golf behaved before the complete failure. While my initial symptoms started with just the check engine light and fuel consumption, I also experienced intermittent rough idling about a week before I had the repair done. The rough idle often indicates that the variable timing system is struggling to maintain proper valve timing, especially at lower RPMs. In my case, the oil sludge buildup in the VANOS solenoid was worse than initially expected, which explained the rough running. Your mileage interval since the last service is relatively low, but VANOS issues can develop even with regular maintenance. When the workshop cleaned my VANOS solenoid, they found that oil quality played a big role, even small amounts of oil sludge can affect the variable timing operation. Definitely get those error codes checked as they will help confirm if your symptoms match what I experienced. A common code for VANOS problems often relates to camshaft position deviations. Based on your current symptoms, it sounds very similar to my situation, and getting it addressed sooner rather than later could prevent more extensive damage.

Thanks for mentioning the rough idle issue, that does worry me a bit more now. The mileage is still pretty low since the last service but those symptoms match up with what you described. Will get the car to a workshop this week to scan those error codes and check the VANOS system. The problem seems to be getting worse, especially the rough idle in the mornings. Starting to notice a slight engine misfire on cold starts too which I forgot to mention earlier. Good to know the repair only took 4 hours in your case, makes it more manageable to plan around. Really appreciate the detailed explanation about the oil sludge impact on the variable timing system. Will make sure to mention all these symptoms when I take it in. Hoping a solenoid replacement and cleaning will sort it like in your case, rather than more extensive timing chain work. Will update once I get the diagnostic results and error codes from the workshop.