VW Lupo Trans Issues: Temperature Sensor To Blame

I experienced similar transmission issues with my 2002 VW Polo diesel. After seeing your post, the symptoms sound identical to what I encountered, rough gear shifting, warning lights, and the car going into limp mode. The gearbox sensor readings were showing incorrect values in my case, but the real problem turned out to be low transmission oil level. The workshop first suspected a faulty temperature sensor, but during inspection, they discovered significant oil loss in the transmission system. The repair involved: Complete transmission oil level check, Replacement of worn transmission seals, Fresh transmission oil fill, Gearbox sensor calibration Total cost was 365€ and it completely resolved the gear shifting problems and warning lights. Before suggesting specific solutions for your Lupo, it would help to know: Current mileage, When was the last transmission service done, Are there any visible oil leaks under the car, Did the problems start suddenly or develop gradually, Does the issue get worse when the engine is hot These transmission issues often start with minor symptoms that worsen over time. Getting it checked early can prevent more extensive damage to the gearbox components.

Thank you for sharing your experience. My Lupo has 131682km on the clock and the last transmission oil change was done about 25000km ago during regular service. The transmission problems started quite suddenly last week, I was driving normally when the warning light appeared and the car went into limp mode. No visible oil leaks underneath, but the grinding noise during gear changes is concerning. Your suggestion about checking the transmission oil level makes sense, especially since the sensor is showing overheating problems. Will have the workshop inspect both the oil level and temperature sensor during the upcoming repair visit. The symptoms line up closely with what you described. Hopefully addressing the oil level and faulty sensor will resolve these transmission issues without requiring major transmission repair work.

Thanks for the additional details about your Lupo. Unlike my case with the Polo where the issues developed gradually, your sudden onset of transmission issues combined with the clean underside suggests we might be looking at different root causes. While low oil levels caused my transmission issues, your problem aligns more with a faulty gearbox sensor. The overheating warnings and sudden limp mode activation are classic symptoms of a malfunctioning temperature sensor, especially since your transmission oil was changed relatively recently at 25000km. During my Polo repair, the workshop mentioned that transmission sensors often fail without warning, triggering false temperature readings and safety mode activation. They recommended checking the sensor connections and wiring before full replacement. A quick tip from my experience, have them check the sensor connector for corrosion. My initial sensor issues were partially due to a corroded connection, which was causing intermittent temperature reading errors. The complete sensor replacement and diagnostic reset on my car cost 220€. Given the similar symptoms, this might be the most logical starting point for your Lupo, rather than jumping straight to transmission oil concerns.

Thanks for sharing those repair details about the Polo sensor issue. Those costs and repair steps give me a good reference point. The timing of my transmission problems does match what you mentioned about sensor failures, it was completely fine one day and then sudden limp mode the next. My workshop appointment is scheduled for next week. Based on your experience, I will ask them to specifically: 1. Check sensor connections and wiring first 2. Test for sensor corrosion issues 3. Verify transmission oil level as a precaution 4. Replace the temperature sensor if needed The grinding during gear shifting is still concerning, but focusing on the sensor makes sense as the first step since it matches the sudden onset and overheating warnings. Will update once I get the diagnostic results and actual repair costs. Hoping it ends up being just a sensor issue rather than more extensive transmission repair work. Good to know about the potential 220€ cost range for sensor replacement. That would be far better than major gearbox repairs. Thanks again for the detailed insights from your similar experience.