My 2005 Seat Leon with a diesel engine has developed a problem. The check engine light is on, and the fuel consumption has increased. I've read that the inlet VANOS mechanics might be faulty, potentially due to a defect in one of the camshaft solenoid valves or a power supply issue. The car has 92202 km on the clock. Thoughts?

Seat Leon Diesel Engine Problem

Check engine light and higher fuel consumption, huh? Sounds familiar. I had similar problems with my Leon, though I've got a petrol engine. I think it might be the VANOS system. I believe the BMW VANOS system shares a similar concept. Does the engine feel like it's lost some power, especially at lower RPMs?

Lost power at lower RPMs, you say? Yes, I've noticed that too. It's not dramatic, but definitely noticeable, especially when accelerating from a standstill. What exactly did you do to fix it?

Yeah, the low power is a telltale sign. I tried cleaning the solenoid valve at first, thinking maybe it was just some oil sludge buildup, but no luck. Honestly, I'd suggest taking it to a workshop. Messing with the camshaft can be tricky, and you don't want to cause more damage. Plus, they can properly diagnose if it's a solenoid or something else. My repair cost around 250€.

Took it to the workshop as you suggested. They confirmed a faulty inlet camshaft solenoid valve. Replaced it, and the check engine light is gone. Fuel consumption seems back to normal. Thanks for the advice.