dont know why i have my answer up twice..
if it only dumps the air with the handbrake off .you may have a faulty brake chamber on 1 of the rear wheels ,or a faulty park brake relay valve ...or possibly a faulty apu ...unfortunately intermittant faults can be a pain ..what you can do is remove the cartridge from the apu (on nearside of chassis )and see if bowl is full of water if so renew cartridge ,as water can play havoc with the valves ..or chock wheels ,run engine handbrake off and see if you can get vehicle to replicate fault ? press clutch see if that cases air loss and same with the brake pedal
norb, February 2012
