Hi Fab-Lab.eu,
I'm not familiar with this sensor but I was checking the datasheet of it. The datasheet mention that SCL and SDA signals needs a pull-up resistor from 2.2 kohm to 10 kohm, and also I'm not sure if the value read needs a proper conversion to get the true value, or if the calibration required is correct. I'd suggest you to take a look to the datasheet in order to check these details: BMP180 Datasheet.
Regards,
Diego.