When its cold, it runs great in forward and reverse, but once it warms up it stalls at red lights and as soon as I put it into reverse. I just got this truck over the summer and have changed the plugs, plug wires, fuel filter, air filter, oil, etc. I read in one of the posts to check the IAC. I took that off and cleaned it good a couple of times already and it is still doing it. I am at a loss now. Any ideas?