I searched this, but couldnt find a thread similar. It was around 10 degrees the other day, the bronco started up fine. My 89 302 idled great, I let it warm up, put it in drive, and the idle suddenly slows down from a steady 800 or so RPMS to erradic around 400 RPMs then it dies. I can restart it, and if I kind of force it to idle high with the throttle, it will drive fine after a bit. Once it warms up, it seems to be fine as well. I havent had a chance to test this during a warm day because its Lubbock and it sucks. The truck has alot of new parts, including new IAC, TPS, and throttle cable. I'm stumped.