hesitation

[raggyo]

i purchased a one owner yaris hatchback, automatic trans. with 37k miles.
i get hestitation sensation at low speeds, however after green light (temp) control is off car rides fairly normal. have been told that this is due to computer taking it's time to analyize gas/air mixture. i have owned car 4 weeks, however it should be noted that we have had heavy rain for the past 3 weeks. car is not garaged. any truth to computer problem?
thanks
raggyo

[johnoh]

Originally Posted by raggyo

however after green light (temp) control is off car rides fairly normal.

If you are saying the car is normal once warm, then you should check your engine coolant sensor. It tells the computer what temperature your coolant is, and therefore what air/fuel mix to use. If it reports incorrectly your car will run roughly until its warm.