I just recently bought a used 2005 chevrolet silverado z71 5.3 and on the very first day I was driving it home and I was on the interstate and all of the sudden on the instrument panel it was saying power loss and the engine would stay running but no matter how much I would press down on the gas pedal it would not do anything all I could do was pull over on the shoulder and turn it off and then I would wait 3 or 4 minutes and it would start right back up with no problem and when I would go to take off again it had full power this happened probably 3 or 4 more times while I was making a 62 mile drive home but while driving it home some times it keep running at full power for longer periods maybe up to 20 or even 30 miles but it just kept losing all engine power and when it did it would only go about 2 to 3 miles an hour but after I would find a place to pull over shut it off it would restart and have full power does any one know what I can try to do to troubleshoot this problem thank you