RE: Truck dies after I let off gas
It could also be your idle air control (IAC) motor. This is usually mounted on the back of the throttle body (not sure on the Rams, however). The name explains it all. The motor moves a pintle in and out of an airway on the throttle body, allowing more or less air thru to control the idle speed.
You can try taking this out (usually held in by two bolts). Clean if needed. Than, with it out, have a friend/wife/kid/etc. turn the key ON (do NOT start the motor!!). i believe the pintle should move.
For the TPS, test the voltage. There should be a steady 5 volts going to it. At idle (butterflys closed), output voltage should be more than 200 millivolts. At WOT, voltage should be less than 4.8 volts. Voltage transition should be smooth. Also, make sure you connect the ground of your multimeter (or voltmeter) to the ground wire of the TPS connector (otherwise, you have no idea if the ground for it is any good).