Random Brake Drag
 

We have a 1983 Porsche 944. While driving along, occasionally the brakes begin to drag; sometimes hard enough to pull the car to one side. I stop and look things over and the brakes release. I take off and can drive for 10 miles, maybe 20, then the brakes begin to drag again.

It happens without even touching the brakes!

It is driving me nuts! What could be happening here?

Thanks

How does the fluid look? The best place to start would be to bleed all of the fluid out and replace.

You may have brake fluid leaking past a caliper seal and causing the pad(s) to grip the rotor. If it always drags on the same side, pull the caliper and pads on that side and check for dampness on the pads and pucks.

An internally collapsed caliper hose is the most likely culprit. When the problem manifests itself, it should be easy to tell which wheel, as it will be significantly hotter than the others. I would start by replacing all the hoses; they're likely old anyway.
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Porsche 924, 944 & 968 (1976-1995) - Brake Hydraulics - Page 4