Thank you all for your offer to help. I did all of the above - over and over. I used (as Prism99 suggested) a double strand of thread) to try cleaning the tension discs. Dang why don't they make the machines so you can open the side (I guess they do on some machines but my Janome 6600 doesn't). It still didn't help. I just kept doing one of the above again and then sewing on a practice fabric and after doing this many times, as I pulled the fabric from under the needle to cut the thread, laying on my table was a piece of thread about two inches long - it was three strands twisted (not tightly) together and ironically two of the strands were white (what was in my bobbin and top as I was sewing) and one strand was gray ( the color I was last using). I have no clue where that came from but just assuming it came from the tension disc. The next line I stitched was fine1 WHEW!!!! Thank goodness.
And thank you all - you have been a blessing to me so many times. Even if I didn't get the help I needed it helped to get it off my chest and get some of your suggestions and hear that the same things happen to others.
Okay - now off to sew.