When i get over 50 mph it bounces between 1400 rpm and 1800 rpm. At first i thought it was not catching overdrive the right way. BUT i pressed off the overdrive button on the shifter and the rpms jumped to 2200 as if it was actually in overdrive. It has a switch that when i turn it on it holds it at 1800 rpm's what causes this

 

What year? What engine? What trans?

 

1998 24 valve idk about the tranny whatever is stock auto with overdrive for the 98 24 valve

 

When I worked at Dodge I had one doing that and it ended up being the electric fuel pump (supply pump for the injection pump). RF interfence to the tps signal in the jtec controller.