Brakes

86 928 After driving about a hour ( with moderate braking ) brakes not releasing at all four wheels all four wheels are hot

your brakes are binding. You need a new master cylinder.

Thanks Trainer It doesn't do it all the time. I drove about 45 miles brakes were OK. Drove about 5 miles applying brake 8 -10 times before it started binding. Car has ABS and my left rear speed sensor is defective it is an early 86 and I can't find a replacement. . Engine bay around master cylinder area was very warm.

When the washers are getting hard in the master it behaves that way. The problem will be intermittent not constant. Change the master and while you are at it you might as well overhaul the calipers as well. The age of the car suggests this is necessary.