VW Eos VANOS Issue Drives Up Fuel Consumption

Had almost the exact same issue with my 2013 VW Golf GTI last summer. Sounds very similar with the increased fuel usage and low power symptoms. The inlet camshaft position sensor was throwing codes and the variable timing system needed attention. After some basic diagnosis, my workshop found a faulty VANOS solenoid valve causing the timing issues. The repair including parts and labor came to 250€. They had to replace one of the electromagnetic valves controlling the variable timing system. The whole job took about 3 hours. The symptoms definitely match what you are describing, sluggish response and higher fuel consumption are classic signs of VANOS failure. Getting it fixed made a huge difference, engine response went back to normal and fuel economy improved significantly. What engine size do you have in your Eos? Also, have you had any diagnostic codes read? This would help confirm if we are dealing with the same issue. Usually, these problems start small but can get worse if left unchecked. Might be worth checking the electrical connections to the VANOS system first, sometimes it can just be a wiring issue rather than the solenoid itself. However, given the age of the car, component failure is quite common.

Latest service was done at 118000km. After replacing the inlet camshaft position sensor the engine misfire and low power issues remained. Took it back to the shop and they found timing chain stretch causing VANOS failure. Very similar to your symptoms. The total repair cost for my timing chain replacement including parts and labor was 1200€. The shop also recommended replacing the VANOS solenoids while they were in there since the engine was already opened up. Performance and fuel economy are back to normal now. Definitely worth getting it checked out properly, these issues tend to get worse if left unaddressed.

This absolutely mirrors my experience when I had VANOS issues with my GTI. When my check engine light first came on, I also tried just replacing the inlet camshaft position sensor, but that was only part of the problem. The timing chain stretch was the real culprit causing the VANOS failure. I had mine repaired about 6 months ago at 125000km, and the total cost was similar, around 1150€ for the full timing chain replacement and new VANOS solenoids. The shop explained that oil sludge buildup had accelerated the chain wear, which is pretty common in these engines. Since the repair, my fuel consumption has dropped back to normal levels and the engine responsiveness is like new again. No more check engine light either. One tip: I switched to a higher grade oil and shorter oil change intervals to help prevent future VANOS issues. Good to hear you got it sorted. These symptoms are pretty textbook for timing chain stretch affecting the variable valve timing system. Getting both the chain and VANOS components replaced together was definitely the right call.

Thanks for the helpful information about the timing chain and VANOS repairs. Just wanted to close the loop on my case. The final diagnosis confirmed timing chain stretch was causing my variable timing issues and affecting the VANOS system. Pretty similar timing too, my Eos had 120000km when these problems started. The total repair hit 1350€ including both the timing chain replacement and new VANOS solenoids. My mechanic showed me the stretched chain and worn solenoids, definitely needed replacing. The check engine light is now gone and the low power issues are completely resolved. Really glad I had this fixed when I did. The shop mentioned the timing chain wear could have caused much bigger problems if left unchecked. Engine performance and fuel consumption are back to factory specs now. Taking your advice about using better oil and more frequent changes to protect the inlet camshaft and VANOS components going forward.