Lumina 1993 has no "choke"

[Joeplante]

The car starts fine in any weather, even when very cold (read snow and -9°C) and idles well. It is even OK when I put it into drive. Now when I accelerate she starts coughing up baddly. If I release the accelerator and stop she still idles fine most of the time.
As she warms up the problem disappears and she runs beautifully.
The symptoms are exactly the same as a carburator gaz engine on which the choke does not work or not used.
All sorts of problems when cold, like fuel starvation, but fine when hot.
Could it be a temperature sensor, which one and where do I find it ?
Thanks for any potential help.

P.S. The car was fully serviced 3 days ago (oil, plugs, wires and filters = $320) and the fuel pressure tested at 49 PSI.

[maxwedge]

Scan it cold and see what the temp
sensor reads.