2001 taurus 3.0 slow starting

Question: 2001 Taurus 3.0 slow starting after it has run and set yet still warm. Takes more cranking time than it used to. If it sits long enough to cool down adequately it fire right off. Approx. 150000on it, changed plugs at 100000. In the mornings it fires of within a second or two of cranking time. If I drive it to work and it sets for a half hour, when I start it it takes 3-4 seconds of cranking time. Have changed fuel filter recently,and have had it in the shop to work on the egr valve and replace a sensor. Answer: I can see two things that will cause this and they go hand in hand. The IAC (Idle Air Control) if it is stuck in the open position, it will cause this issue. The other is a engine temp sensor( not the coolant temp sensor) as the the computer uses the reading from the engine temp sensor to adjust the IAC.