when it is cold out, my 99 crown vic will not go to high idle when you start it, on 1999 Ford Crown Victoria

it blubber and dies. it take sitting in car with foot on gas pedal for 5 to 10 minutes before it will stay running but if it's warm out it starts like brand new car. any ideas?

Asked by for the 1999 Ford Crown Victoria
Coolant tempture sensor! Can be tested with a scanner, not a code reader.