My FJ60 runs great when it's cold. It idles fine and drives great. However, for some reason or another, after it has been driven for a while it will continue to run fine as long as you keep moving, but will stall out at a stop sign or stop light. In order to keep it running I have to keep my foot on the gas. If I don't, the idle drops all the way down and my truck dies. Can someone tell me what is going on? I've only had this truck for a short period of time, and have done a little work on it. I also had a Toyota specialist (not a dealership) look at it and do some work on it as well. I have no idea what is wrong. Please help!