Most vapour locks are caused (in the engine bay anyway) by heat soaking up from the engine mass and boiling the fuel in the lines. This vapour can then act a gas, preventing liquid fuel reaching the injectors. In theory the accumulator in Kjet maintains enough pressure in the lines to prevent this, but it only works as long as there is no leakage path allowing the pressure to drop (ie leaking cold start injector, or main pressure regulator valve). Trying to get fuel by popping the CSV wont help deliver fuel if there is only vapour in the line, but it may alllow the vapour to dissipate?
jp