2014 Wester Star dd16, won't start after shutting it off.

Ck all the grounds and look for water leaks around FT. windshield that let water run down inside of firewall and cause green cancer to ruin all conn. That it gets on, you can make duck tape V Shaped water dams that send water away from plug in conn. Where wires pass thru firewall?

 

You can ck. The voltage coming from T P S to see it rise to 5 volts at full petal and close to. .54 at idle and you can see it rise evenly thru the full travel of fuel pedal? If when you unplug the TPS and put the factory test plug in with connectors to put a voltage test multimeter in its easy to test, but you can make one with wires stripped in not even spots so that you don't short out tps and end up buying more than one tps?

 

Need to focus on what all those symptoms have in common. Like a common ground, etc.

If you post the last 6 of the vin, I can show you some wiring diagrams.