Audi S1 Trans Sensor Failure Causes Emergency Mode

I had a very similar issue with my 2013 Audi S3, which shares many components with your S1. Being someone with some mechanical experience, I first tried basic diagnostics but quickly realized this needed professional attention. The symptoms matched exactly, poor shifting, grinding noises, and transmission warning lights. The sensor fault initially pointed to the pressure sensor, but when the workshop did a thorough check, they discovered the root cause was actually low transmission oil level, which triggered the sensor warnings. The repair involved: Complete transmission oil level check, Cleaning the oil pressure sensor, Topping up with specific transmission fluid, Full system diagnostic reset Total cost was 365 Euro and the car has been running perfectly since. The whole job took about 4 hours. Before suggesting any specific fixes for your case, could you provide: Current mileage, When was the last transmission service, Does the grinding noise happen at specific speeds, Any other unusual sounds or behavior These transmission issues can cascade into bigger problems if not addressed quickly, especially when oil pressure and sensor readings are involved.

Last service was at 65000KM so Im already overdue for the next service interval. The grinding noise mainly occurs during gear changes from 2nd to 3rd, and its most noticeable when the engine is cold. The transmission fault appears to be getting worse and oil pressure warnings are now more frequent. The oil level seems fine based on the diagnostic readout, but the pressure sensor continues showing erratic values. Called two workshops and both mentioned similar cases where faulty pressure sensors caused these symptoms. Need to book it in soon before the transmission gets damaged. A full diagnostic test and pressure sensor replacement has been quoted at 450 Euro. Want to get this sorted quickly as its my daily driver.

Thanks for those details. After fixing my S3s similar issues, I can definitely add some insights here. While our initial diagnosis on the pressure sensor seemed solid, your symptoms point to a potentially more complex issue. The oil level being fine but getting erratic pressure readings matches exactly what happened in my case before things got worse. The cold weather grinding between 2nd and 3rd is particularly telling. When my transmission sensor was failing, it would cause similar issues, especially before warmup. The fact that your pressure readings are becoming more frequent suggests the sensor degradation is accelerating. The 450 Euro quote for diagnostics and pressure sensor replacement sounds reasonable. My repair ended up including: Transmission oil pressure sensor replacement, Full system pressure testing, Transmission oil level verification, ECU adaptation after sensor replacement Based on how the symptoms match, I would recommend getting it done ASAP. The erratic pressure readings can cause the transmission control unit to apply incorrect pressure, potentially leading to internal damage. After my repair, the grinding completely disappeared and shift quality returned to normal. Just make sure they perform a complete adaptation procedure after replacing the sensor. This helps the transmission control unit learn the new pressure switch values properly.

Looking at the feedback and sharing the symptoms, I think getting this fixed quickly is the right call. Since Im already past the service interval and experiencing worsening transmission fault warnings, waiting longer could lead to bigger issues. The grinding between 2nd and 3rd matches what others experienced with faulty pressure sensors. The increasing frequency of oil pressure warnings definitely concerns me, especially since the transmission sensor readings are all over the place despite normal oil levels. The 450 Euro quote seems fair compared to other repair costs shared here. Will book it in next week and make sure they do the full procedure including: Sensor replacement, System pressure testing, ECU adaptation, General transmission inspection Good to hear these symptoms were resolved after fixing similar pressure switch issues. Better to address it now while its still mainly a sensor fault rather than risk actual transmission damage. Will update once the repair is done.