Here is a picture of fluid pressure where arrows indicate the location of the start point and the self contact area. Pressure should propagate from left to right as elements get out of contact. However, pressure is also applied on the right area directly at the start, which should not happen (because no start points are located there).
I did plot the fluid pressure with only contact between solids selected, which gives the result that I want :
Then I switched to self contact and I do get this :
I think that the commands "cmsel,s,Pressure" and "esel,r,type,,cid_1" select all the contact elements that are in the "pressure" named selection. To solve my issue, I should only select the correct contact elements.