VW Throttle Sensor Failure Causes Power Loss & Lag

I experienced a very similar issue with my 2003 VW Golf with the 1.6L gasoline engine. As someone with some experience working on VWs, these symptoms immediately pointed to throttle body issues. The symptoms matched exactly, sluggish throttle response, delayed acceleration, and the car went into limp mode. The check engine light came on and fuel efficiency dropped noticeably. After attempting basic diagnostics like cleaning the throttle body, the issue persisted. Took it to a workshop where they diagnosed a faulty accelerator pedal module. The electronics inside had failed, causing erratic throttle response. The total replacement cost was 265€ including parts and labor. The repair resolved all symptoms and restored normal performance. Before jumping to conclusions though, could you share: Engine size/type, Current mileage, When was the last throttle body cleaning done, Any other warning lights besides check engine, Does the problem occur more when the engine is cold or warm This information would help determine if your issue is similar and whether you might need the same repair.

Thanks for the detailed information. My car has 93805km on the clock and just had its annual service last month. No other warning lights besides check engine. The problem seems consistent regardless of engine temperature. I tried cleaning the throttle body as suggested but the poor throttle response persists. The air flow meter readings from my OBD scanner look normal, which makes me lean towards your theory about the pedal module. If the replacement cost is around 265€, that seems reasonable compared to what I feared. Did you notice any immediate improvement in fuel efficiency after the repair was done?

Yes, I noticed a significant improvement immediately after replacing the accelerator pedal module on my Golf. Fuel efficiency returned to normal levels within the first tank, and the throttle response became crisp again without any delay. Your situation sounds nearly identical to what I experienced. The normal air flow meter readings combined with persistent throttle response issues despite cleaning strongly suggest the pedal module rather than a throttle body problem. When my pedal module was failing, it would send incorrect signals to the ECU, causing the engine to run in a reduced power state. The limp mode and check engine light triggered because the ECU detected inconsistent signals between the throttle sensor and pedal position. The replacement cost I quoted included diagnostic time, but some shops might charge differently. The part itself was around 180€ if I remember correctly. Just ensure the workshop uses OEM or high-quality equivalent parts. My repair has held up perfectly for over 40000km now with no recurring issues. The improved throttle response and restored fuel economy made it well worth the investment.

Thanks for all the helpful details. After what you described and comparing it to my symptoms, I feel more confident about the pedal module being the culprit. The consistent poor response regardless of temperature and the normal air flow readings match up perfectly with your experience. I called a few workshops and got quotes ranging from 250€ to 290€ for the repair, which aligns with what you paid. One shop can take my car tomorrow, so I will go ahead with the replacement. The potential fuel efficiency gains alone make it worthwhile, not to mention fixing the frustrating response delay. Really appreciate you sharing your repair experience. Will update once the work is done to confirm if the pedal module fixed the issues. Hoping for the same positive outcome you had with restored performance and better fuel economy.