After reading and investigating, I realised that the temperature gauge never went over 70ēC when driving in motorway and went up stuck in a traffic jam. Therefore, my thermostat was always open and never reached 90ēC.
So, I bought a thermostat (100Eur-Valeo), removed the temperature sensor from the existing stat because the one that came with the new stat did´nt work correctly.
And after 2 hours of work the result was successful!!!! Now my alfa runs better, gets to 90ēC in 3 minutes.
I would like to point out the following that helped me from other threads:
- Changed original Alfa clic hose clips for jubilee clips.
- Removed the battery as specified in the workshop manual which eased the work.
I am happy, as this was my first job in the car and will keep on doing Glow plug replacement!