I have a 2001 ram diesel with 83000 on it. While driving it ,I lose power like the throttle isn't working . but the truck is running fine. I push harder on the throttle pedal and it finally starts to move. At no time does the truck stop running. I have changed the fuel filter and it did not change things. I have notice that it doesn't seem to happen when it is out of OD,or in towing mode. Need help

 

I'd start with the TPS. Are you getting any CELs???

 

But can you tell me what is TPS and CELS ?????