I have built a little thermostat based on [BMP280][1] temperature sensor over I2C, ESP8266 Lolin v3 and STX882 433Mhz transmitter.

I have not added additional pull-up resistors or decoupling capacitors.

Everything works fine when the components are out of the enclosure (see picture), but when I put them inside the enclosure the BMP280 readings start to 'oscillate' as shown in this picture[![See the oscillation after 18:00. Ignore the spikes, that was me touching the sensor.][2]][2] 

I am not an electrical engineer and the only thing I can think of is that there is some kind of interference between the transmitter and the BMP280 or I2C bus.

To give you and idea I am also attaching two pictures of the thermostat.
[![Closed enclosure][3]][3]
[![Open enclosure][4]][4]

Any suggestion?

EDIT:
It was sufficient to move away the RF Transmitter. I have actually hidden it under the LoLin.[![Smoother chart][5]][5]
[![enter image description here][6]][6]


  [1]: https://startingelectronics.org/pinout/GY-BMP280-pressure-sensor-module/
  [2]: https://i.sstatic.net/1RbVp.png
  [3]: https://i.sstatic.net/zMy2e.jpg
  [4]: https://i.sstatic.net/qMlUo.jpg
  [5]: https://i.sstatic.net/lW3Cr.png
  [6]: https://i.sstatic.net/ELCBB.jpg