1994 GMC Safari Engine will not cold start easily. Runs

This is the same as a Chevrolet Astro for that year and equipment.

When weather was cold would be hard to start. Once started, ran perfectly. Gradually became harder to start until now, will rarely start when engine is cold. Shot of starter fluig will ALWAYS make start and run fine. Starts every time when engine is warmed, even for only a minute or so. It cranks fine and forever. Voltage seems correct when cranking (10.6+), but changed battery anyway (new).

- No Check engine codes thrown, none ever (light does work. ECM dumped, no codes shown BEFORE battery was changed).
- Battery changed
- Fuel pump relay changed. (Also leads shorted to make pump run continuously and still does not start. I had thought the relay was not operating or staying operated on cranking.)
- Plugs changed (Old plugs did have large gap.) Rotor changed, cap changed. No noticeable arcing in the dark. Spark is VERY good while cranking. (Pulled a wire and put a plug in it.)
- Pulled ECT (coolant temperature) sensor wire (giving it positive high resistance. Thinking, if it was shorted maybe ECM is thinking engine is warm and not supplying richer starting mixture, which really seems to be the issue. Starts every time with starting fluid. No difference and no code shown.)
- Fuel pressure gauge on Shrader valve measures withing spec but on the low edge (55 psi) but stays there for at least 15 minutes after pump runs if no starting is tried. It stays there when cranking, but needle vibrates a bit around that number while cranking.
- Runs well and goes to very high speed and climbs steep hills with no issues when running.
- Fuel filter was replaced as well.
- W engine code, Vortex.