On my R25 I checked everything this afternoon. No pipe cut, no fault on the electronic elements (sensors and co.) Confirmed by the Renault garage, absolute pressure probe OK ... etc
In the end, I think it comes from the pressure (and idle) regulator which is located under the intake pipes between the electric fuel pump and the injectors. There is a bypass that sends gasoline in a " basin "located at the bottom of the intake manifold. it's been a small bowl and I noticed that there was gasoline at the bottom even when the engine had just run on LPG !! weird I said to myself !!
So I put in petrol mode and I disconnected the small pipe which sends this petrol into the intake manifold (for idling needs I suppose), and there I saw that it flowed a lot ... .. hence slowed down to 1300 rpm impossible to adjust lower with an irregularity.
However I saw in the home page of the website of the R25 (club) that the idle speed regulator in question (if it is him), does not have a long lifespan (150000kms max). .or my 25 to 300000 km, and it hasn't been changed since I got it at 160000 km.
So tomorrow, I get another one that I have in my parts inventory and I will mount it in place of the old one.
We'll see if it works. In my opinion that is the problem. In addition I do not know if when I switch to LPG mode, the fuel pump is short-circuited but I believe so, because at idle in LPG, it does not come out of gas through this little hose. to be continued. I'll talk about it on the forum R25ists.
Only when he has brought down the last tree, the last river contaminated, the last fish caught that man will realize that money is not edible (Indian MOHAWK).