Maxxforce 13 throttle problem

I have a 14 Prostar with a maxxforce 13. The truck was getting poor fuel economy. So we replaced the fuel filters and the air filter. Since replacing the filters the truck acted like the turbo had failed. It had no power and was blowing black smoke out the exhaust. I shut the truck off checked to see if there was oil in turbo inlets everything was fine. Started the truck back up and it ran ok. No power lose. But today the truck acts like its governed at 63MPH. So from idle I can only rev engine to 1375 RPMs. The truck is pulling fine up to 1375 rpm. Then its like a dead pedal. If I cycle the key really fast I can rev truck to max rpm and I can accelerate to max governed speed of 80 mph. Has anyone experienced this? Is it the engine throttle valve?

 

This is the first problem I've had so far that I can't figure out. Its been a solid little engine since I've had it.

 

I replaced the fuel pump back in Dec. And there aren't any fault codes for me to go off of.

 

I replaced the fuel pump back in Dec. And there aren't any fault codes for me to go off of.

 

Would the speed sensor cause a problem like this?