Just changed my oil pressure sensor to fix oil leak. [You must be registered and logged in to see this image.]
Originally thought it was crankcase grub screw leaking but after looking harder & pulling tank it was clearly the oil sensor.....weirdly, after spending ages getting deep reach 21 mm socket, the sensor was light-finger tight (it's supposed to be 24 nm) there was no washer either...so amazed it's taken 10 years and 36k miles to start leaking.
Thanks Guzzi Cat for the MR Auto link BTW …sadly BMW dealer couldn't find the right sensor despite giving them the same model/year that finds the right one on Mr Auto & Euro parts site ….BMW parts guy said they needed the registration or VIN number of the car to be sure..... So got £10 one from Euro Parts. [You must be registered and logged in to see this image.][You must be registered and logged in to see this image.]
Only issue was BMW one is 23mm and very deep head; so had to tighten it to approx 25 nm torque with mole grips turned using adjustable spanner (not my best engineering moment)...