1999 Peterbilt 379 Speedometer Bounces

Yes.

 

But my cruise will not idle up the truck when sitting still , that’s what we can’t figure out

 

Yeah, because the pulse wheel is vibrating around and the ECM pics up on that. Start with my first reply. If you ain't gonna listen to those who reply, don't ask

 

Check the wiring from the speed sensor for abrasion or corrosion. If the problem started when the speedo was changed the problem might be with the speedo settings. The ecm gets input from everything and if something disagrees with everything else nothing works right.

 

And if no one has put a socket on the nut it hasn't been checked.

 

Hey brother I understand, and I will not problem here . I appreciate all your input . I will try and let you know what I find out thanks again