Hey I don't know if have fix ur truck! If not is the engine light on on the cluster? If so get someone to hook it up and pull the codes. If it's not on, when you turn the key to the on position an the gauges on the cluster are jumping back and forth will the windshield wipers work or will the windows roll down if they are electric! But what I have read from your question it sounds like the ECM/ECU is bad! You can pull it out and have it checked. It's easy to pull it out! Just pull the glove box it's two screws just under the dash. Then you will be looking at the computer. Also you might pull the computer and on top of it there will be two screws pull them and make sure the chip is in it or make sure it's pushed all the way in! Just something to try! Let me know!