I have a 2001 F25 with the 7.3L. Recently I've encountered some kind fo electrical problem. I think. When I bring my truck to a stop and put it in park the truck will rev the engine up to about 1300 or 1400 RPM for a few seconds then settle back down to idle. Also one time while stopped and in park the speedometer started jumping all over the place. I have a DP Tuner. The truck will do this when I have to tuner on and when I have the tuner off. I don't know where I need to start looking. Can someone point me in the right direction of where I need to look to fix this problem? I can answer any further question y'all might have. I recently replaced the speed sensor because it threw a code and was hoping that would fix the problem and it didn't. Thanks for your help.
I think my problem is linked somehow to the trailer brake controller. I leave my controller unplugged when not in use. I only have the symptoms when I plug my controller in, with or without a trailer. At this point it makes no sense to me.