Ok here is the deal, I am a good backyard mechanic but I am in need of some technical help, this is my situation. I am up here in the NW, right now it is cold in the mornings when I leave for work. Truck starts up just fine, but idles real low, 800. By the time I get to work the engine is all warmed but the idle is now sitting between 1400-1500, I just recently replaced the carb with a prof. rebuilt one, everything went together fine, all vacuum lines are ran (according to the vacuum diagram), so I am kind of lost on why the carb is acting this way? Gas milage is down a bit too.

OK here is one more thing I just remembered! while the truck is running, when ever I tap the break pedal, my running lights come on, anyone know where to start looking for the short? I am assuming that is what is causing it?

Thanks again. <img src="/forums/images/graemlins/kewl.gif" alt="" />

whenever you start the truck cold fully depress the gas pedal once or twice to engage the fast idle and choke. it also gives it a richer mixture which is good for the engine when its cold. after that it should idle at 1500 rpms or more until warm. if your truck is warm and it still idles up high you can usually stomp the gas for a second to get it back down to the normal 750-900 rpms.

This is kinda a dumb one but check the throttle linkage on the carb, mine sitcks for some reason and every now and then I have to give the throttle a little 'blip' to unstick it.

The brake/running light thing sounds like a short between the brake light wires and the running light circuit. Start at the tail light sockets and work your way forward along the brake light wires. If you have wiring for a trailer, its probably part of the problem.