I would not think your problems have really anything to do with the TSS. Actually, if you read Hightowers original post and then Fastcougars first post in his "1-2 Bang Shift Gone" thread, you will find that the bang shifting that they are talking about it a harsh shift that happens from first to second at almost WOT conditions if you release the throttle just before the shift into second. All the the clams of smoother shifting are just what I call "profit claims". That is not to say that I don't believe any of them, because I do. But this is not why the subject was first brought up. The reason I call them "profit claims" is because not only did they solve the original problem, but also was able to see improvments in other areas as well.
Now, for your problem, I would have to go with the range sensor as my first guess. No other reason I can think of for your tranny to shift from 1st to 4th like that.
Here is a picture I posted a few days ago that might help you locate the range sensor...
... it is in line "A" item "280". On the tranny, it is located on top, just under the water pump. That should give ya a pretty good idea.
Also, check my
links page for some more technical articles. I know that I have a link to a ASTG search that I did. That link contains several articles that covers a lot of detailed info on the CD4E and on article inpertecular that covers troubleshooting the range sensor. If you have any problems finding it, just give me a holla and I will be happy to find it for ya.
Oh yeah! Did it set a CEL or anything when this happened?
[EDIT]Oops! I forgot to put the link to my links page...

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