The injector does not close fully, and with the engine standing fuel drips into the cylinder. The symptoms are hard, long cranking (mostly after standing for a while), smoky first minutes, a hesitant idle, and dilution of the engine oil: the oil level goes higher, it smells of petrol, and the diluted oil lubricates worse. It shows up on cars built between 2018 and 2020.
What to check
- Start it cold after standing for a while: several seconds of cranking and blue-white smoke are suspect
- Pull the dipstick: a level rising above MAX and a petrol smell indicate dilution
- Smell the oil filler: a petrol smell means fuel has got into the oil