Random high idle
I have a 2003 4.6 V8 and every so often after starting the truck it will sit at 2000 or more RPM. This happens in park and neutral. Even if I drive it or reverse it when I come to a stop and shift to park/neutral the RPM will climb from 1.5 to over 2.5. I've tried cleaning the throttle body in case it was just sticking but to no effect. Any advice?