On my 92 940 non turbo some times the break peddle is horrid, going almost to the floor. Some times its 100% normal. Any ideas?

 

Sounds like it's time to replace the master cylinder. I say this because if it was a caliper problem or a leak it wouldn't just do it some of the time, it would do it all of the time. If your brake fluid hasn't been changed in a while I've seen where flushing it out can cure brake problems like you're describing. Rust gets into the system and can cause the master cylinder seals to leak internally.