Residual air...??? I`m guessing for that to exist that the suggestion might be that system may not have been properly bled... As I have typed previously, I have bled an ABS system using gravity only, which worked well enough.
I guess with ABS it may be possible that if part of the system has been drained, air could be trapped behind a closed valve and not released back into the system until the ABS is activated for the first time after the drain down...?
