Toyota Repair: brakes, caliper design, bolts

Question
bled all brake lines,replaced booster, pads o.k. on 89 toyota p.u.....have no brake pedal pressure. comes and goes
while bleeding. is it master cyl?

Answer
Check to make sure that the caliper pins are not binding up, this uses a floating caliper design that causes the caliper to move on pins as the breaks wear down, if the pins are rusted and sticking it will cause a loss of brake pedal, remove the 17mm bolts at the back of the caliper and pull them out and clean and lubricate these.