1981 240:

My car has developed an issue with the brakes. Sometimes it acts like the power assist isn't working. Other times it acts fine. I can find no vacuum leaks that would affect the power booster. I can find no fluid leaks either. Also, sometimes the pedal travel is less than other times. The symptoms are inconsistent. The car always stops, but sometimes I have to apply more pressure to the pedal to make it stop. Any diagnostic and/or repair tips would be greatly appreciated. It doesn't feel like it just needs a brake bleed.
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Thanks for all the help. DougC ::::: 1981 242, IPD bars and Turbo wheels, M46:::::::1984 760, B23FT, M46, waiting to donate engine to 242:::::::1997 S90

You may want to check the wear on the Pads.
Check the wear on the Inner pad as compared to the outer pad on each wheel.
Perhaps a piston on the caliper is intermittently hanging up. A frozen piston would give you a stiff pedal.

Does this only do it when it's below freezing temperatures?

Check cleanliness and lube on the Slide pins, maybe one pin is hanging the pad up a bit

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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.lyse.net/brox/TonyPage4.html

Thanks for the advice. Still not sure, but I think it's the booster that has failed. I'll know soon when I replace it with a known good one.
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Thanks for all the help. DougC ::::: 1981 242, IPD bars and Turbo wheels, M46:::::::1984 760, B23FT, M46, waiting to donate engine to 242:::::::1997 S90

Maybe the booster check valve is sticking? It just seems to be a flap.
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1980 245 Canadian B21A with SU carb but electronic ignition and M46 trans in Brampton, Ont.

Check valve turned out to be fine. Will try a known good booster. Thanks for the tip.
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Thanks for all the help. DougC ::::: 1981 242, IPD bars and Turbo wheels, M46:::::::1984 760, B23FT, M46, waiting to donate engine to 242:::::::1997 S90

Doug, before you go to the trouble of changing a booster, try replacing the vacuum hose if you haven't. I ran into this hose that was a bit soft at the manifold end, collapsing like an asthma sufferer's windpipe.
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Art Benstein near Baltimore

If speed counted, rabbits would rule the world.

Hi Art,

Already tried a new check valve with new vacuum hose. No help. Thanks for the tip.

Doug
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Thanks for all the help. DougC ::::: 1981 242, IPD bars and Turbo wheels, M46:::::::1984 760, B23FT, M46, waiting to donate engine to 242:::::::1997 S90