for a while, I am not able to complete a full cycle of self-learn on my Challenge stradale. (I am using a leonardo. ) It always runs out of f1 pressure at some point, maybe 3rd gear or 4th gear and resume "clunking" when it is at 6th gear. Car drives fine. I want to get to the bottom of it. What caused this?
Have you checked to see when the pump runs? It is supposed to be charging the accumulator when the pressure gets low. There could be a problem with the pressure switch that controls the pump relay. The relay is a known problem area, or the pump/motor itself could be a problem. The accumulator gets low on charge over time, causing the pump to cycle too quickly, or their could be leakage in the system also allowing leakage. The first thing to do it just see if the pump is running when you run out of pressure and then go from there.
there's no pressure leakage as evidence in the pressure drop rate read from leonardo. Yes, possible about the pressure switch. It almost as if the switch won't turn on until 10 seconds after pressure drops to 40 bar. But I always thought this is a TCU control issue, not a physical part issue.
Yes..top side almost at the base of the accumulator. The switch has a completely different connector then the rest.
Also, make sure the battery is fully charged, if the voltage goes below operating threshold, it will cause an error.