VW Sharan Throttle Issues Spike Fuel Consumption

Had a similar issue with my 2014 VW Touran diesel a couple years back. Based on my experience with engine maintenance, these symptoms sound very familiar. Initially thought it was just a dirty throttle body and tried cleaning it, but the real culprit turned out to be a defective accelerator pedal module. The symptoms matched exactly what you describe, poor fuel efficiency, unstable idle, and delayed throttle valve response. Took it to a workshop where they first performed diagnostic tests to confirm the issue. The repair involved replacing the entire accelerator pedal module, which cost 205€ including labor. After the fix, the throttle control returned to normal and fuel consumption dropped back to regular levels. Before jumping to conclusions though, would need some additional information about your case: Any warning lights on the dashboard? Does the engine management light come on? Have you noticed any specific driving conditions when the problems are worse? When was the last throttle cleaning service performed? Getting this info would help determine if you are dealing with the same issue. These symptoms can sometimes be related to other problems in the air intake system or fuel delivery components.

Last service completed at 116000km, roughly 2 months ago. Just had the car checked at workshop after seeing these responses. They confirmed it was indeed the throttle body causing the poor engine idle. The control valve was sticking due to carbon buildup. The mechanic performed a thorough throttle cleaning service which resolved most issues. Total repair cost was 180€ including diagnostics. Car throttle response is now much smoother and fuel consumption has returned to normal levels. Thanks for the detailed input about the accelerator pedal module, will keep that in mind for future reference. Currently monitoring the situation but so far the cleaning seems to have fixed the problem.

Good to hear you got it sorted through throttle cleaning! My Touran had similar carbon buildup issues over time that affected engine idle performance. Regular cleaning of the throttle body and control valve is crucial for these engines to maintain proper fuel efficiency. Since your service was recent, make sure to keep track of how the engine idle behaves over the next few weeks. In my case, I noticed the cleaning effect lasted about 18-20 months before minor symptoms started showing again. Now I schedule preventive throttle cleaning every 40000km to avoid performance issues. One tip that helped reduce carbon buildup in my car: running the engine at slightly higher RPMs for a few minutes during longer drives. This helps clear out deposits before they accumulate too much and impact the throttle response. The 180€ repair cost sounds reasonable considering the diagnostic work involved. Much better than having to replace the entire throttle body unit which would have been around 600€.

The throttle cleaning service turned out to be exactly what my car needed. After having it done, the engine runs much smoother and the fuel consumption is back to normal levels. The mechanic showed me the carbon buildup they removed from the throttle body and control valve, it was substantial. The total cost of 180€ for diagnostics and cleaning was reasonable, especially compared to a full throttle body replacement. Running the engine at higher RPMs occasionally to prevent buildup makes sense and I will definitely try this approach. Currently monitoring the throttle response and engine idle behavior, but after two weeks everything seems stable. Planning to schedule regular throttle cleaning services going forward to maintain optimal air intake system performance. Will set a reminder for the next cleaning at 40000km as suggested. Thanks for all the helpful advice about preventive maintenance. The workshopas thorough and the cleaning service fixed the issues without needing more expensive repairs.