Here is what I think is happening.

The vaccuum "bleed-off" valve on the top of the valve cover, this valve prohibits vaccuum from getting to the trans modulator. When you touch the throttle, the valve opens and receives a large vaccuum signal, and you get 1st gear.
I suspect that someone was monkeying around with your vaccuum lines trying to get it to shift better.

I noticed that if I eliminate all vaccuum from the modulator, IOW, block a signal from the modulator, The trans will not go into 1st by itself.
It will go in if you use the lever. But it won't shift into second until redline. Here is what you can do. Push the lever from L to S, this will shift it into second. Quickly, shift it back to L and it will stay in second. If you leave it in S, it will quickly go through second and into third, leaving you with little acceleration.
You will get the hang of it.

Hope this helps,
Ed

__________________
Ed
1981 300CD (Benzina)
1968 250 S (Gina) 266,000 miles!
1983 Alfa Romeo GTV6 (Guido)
1976 Jaguar XJS-saved a V-12 from the chevy curse, what a great engine!
1988 Cadillac Eldorado (better car than you might think!)
1988 Yamaha Venture (better than a Wing!)
1977 Suzuki GS750B
1976 Yamaha XS 650 (sold)
1991 Suzuki GSX1100G (Shafty Gixser)
1981 Yamaha VX920RH (Euro "Virago")
Solex Moped
1975 Dodge P/U camper


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