1994 Olds 88 ABS Brake Problems

A rear brake caliper was replaced last fall. This winter, during the cold weather, I experienced brake problems at start up. Brake pedal goes rock hard and has to be pumped as many as 5 or 6 times before putting the car in gear. Then the pedal goes back to normal and works fine the rest of the day unless it sits for 4 or 5 hours in the cold weather. We tried bleeding the lines (more than once) but apparently there is a (complicated ?) sequence of steps to follow to do this. Anyone know where I can get this information. Thanks

Did it do this before you replaced the brake caliper?

Hi, Thank you for your time. The car is usually garaged in the winter. Now that I think back there were a few times (5 or 6) in the last couple of years that I would be backing out of the garage and had no brakes. Figured it was from sitting in a damp garage. A couple of pumps and they would work fine. Car has pretty much been outside all of this winter. Thus, everytime I use it I need to pump the brakes. We have tried bleeding the lines on a few different occasions. Husband is well qualified to do this. Seems no matter what we do it doesn't fix the problem. I know that the brake lines may criss cross to each wheel when they come out of the master cylinder. Thinking there is a certain order to follow when bleeding the lines.