Don't see to matter if it's cold or hot, when you start it, it tends to just slow die watching the tach!If it does staying running it also does it when u bump into to reverse. Car is a Auto, mind you! Dont' do it into drive that she has told me, just in park and R, it has done it to me so, i know she's not fibbing...LOL any help would be good!!
Sounds maybe like some fuel issues such as the fuel filter or pump. Id have it checked for pressure. If you dont have enough pressure then you know its either of those 2. It probably would be a good idea to change the fuel filter anyway.