It will start cold, run, but when warms up, won't idle, shuts off.

already did that; also changed computer; put new throttle positioning sensor in; checked spark; put all new relays in; Not sure what else to try. Any other suggestions would be great!! Thank you.

Check engine light should be on... Learn how to get flash codes by checking out YouTube ... Post codes and we will try to help!

we pulled the flashing codes and looked up code numbers. code says it was the Cooling Temperature Sensor. bought new part for $18 and truck runs fine. Thank you all for your help.

You bet!! .....glad you got it fixed!!!!

Do not need a scan tool! It will flash the codes if you follow the YouTube video!... Key on... key off... key on.... Key off... Now leave Key on... Read flash codes... See YouTube!!!!!!