2003 Ford Crown Victoria (police edition) 4.6 Ltr.

Vapor lock? Not sure, here is my problem. Only happens when it is hot out, and I've been driving around a lot! Engine temp is half way, which looks normal, I still need to get this checked out though, and veirfy if its vapor lock? Leaving the winter season no probs running! Now that it is greeting nice out, I almost forgot about the problem when it happend again to me yesterday. After its been running and I shut it down, it wants to stall out when I try to start it? If I start it and put some gas pedal to it, it has an unusual high rev, almost like its not running on all cylinders? Had to do this to get out of traffic once, not good! To put it in gear with the break and giving gas to it, but it was the only way to get it goin, but still wanted to stall out! Wish someone could help you, and help me! This is the type of situation I would have to take it into a mechanic right at the time that it is happening, otherwise they wouldn't know what to look for?