Thanks for the information. I did try the procedure just as explained the first time with a cold engine (not driven in a day cold) and did not get much Seafoam in the line, nor did I get the white smoke. So letting it sit over night, I thought I would try again. After reading another post here, DMAX mentioned a clogged hose. So I removed the hose to check for any blockages or holes. When I removed it, liquid spilled out, but the hose was in good shape and not blocked. I put it back on and filled the tube with Seafoam. I started the car and I wish I had a picture of the white smoke that came out of the tail pipe -- it was unbelievable. I let is idle for about 10 minutes and the smoke eventually cleared. Then I went for a drive. Drove perfect for about half mile and started misfiring again.
I think that I will try this again tomorrow and also listen for the whining pump sound on cold start. Thanks for the good advice. I will continue to chase this and post my eventual findings. I just hate to start replacing a bunch of good parts, but I am convinced that the issue is fairly minor.