2002 ih 8100

Bought this truck with the following problems, starts and idles fine, no throttle pedal for a couple mins. When the pedal does start working there's no control. It continues to rev up no matter where i hold the pedal until I let up on the throttle pedal.

Also the dash doesn't work, (tach and speedometer do work) the gauges sweep when the key is turned on but return too off positions. Gauge cluster looks new. The previous shop had put a whole new engine harness on but no luck.

could the two problems be related, also both the warn and stop engine light are on. Cummins ISM engine.

 

The truck diagnostics shows no fault. I dont have a scanner