mchwolvrne

Working on a 90 probe lx brakes. Have bled brakes and found no leaks, pedal is still going to the floor. This only happens during the colder parts of the day. When the outside temp is above 65 or so, there are no problems. I suspect something is wrong in the master cylinder. Have went through all suggestions of Haynes manual and this is my last resort. It does loose fluid but can't find a leak at any of the calipers. Any suggestions......

billproctor

My first thought would be the master cylinder. check the power booster to see if the fuild is leaking around where the master cylinder is attached. Check the rubber hoses going to your calipers also and check to insure that they are not collapsed.