Seat Altea Fuel Consumption and Starting Issues

I had a similar issue with my Seat Altea, though I can't recall the exact year of manufacture. It presented with higher fuel consumption and difficulty starting, much like you describe. Have you checked the throttle position sensor readings? A faulty sensor can definitely cause these symptoms. It would be beneficial to ascertain if the control valve is operating correctly. Is the engine throttle responding smoothly to changes in pedal position, or is there any lag or hesitation?

Thank you for your reply. I have not checked the throttle position sensor readings myself, as I do not have the necessary diagnostic equipment. However, based on your experience, is it plausible that a defective accelerator pedal module could be the root cause, and not necessarily a dirty engine throttle?

Indeed, a defective accelerator pedal module is a strong possibility. While throttle cleaning might offer a temporary improvement, it is unlikely to resolve a fault within the module itself. Given your description, it would be prudent to have the throttle position sensor and the accelerator pedal module professionally diagnosed. I ended up having to replace the accelerator pedal module in my Altea. Considering the mileage on your vehicle, it's a common failure point. I'd recommend taking it to a reputable workshop for a proper diagnosis and repair.

Thank you for your assistance. The workshop confirmed the diagnosis, and the repair, including parts and labor, came to 205€. Fuel consumption seems to be back to normal, and the engine starts much better now.