Depends, a lot of the chevy deisels, fuel injecter pumps go out or start to go out and can cause that problem, first thing you need to do is check the map sensor on the top of motor under the cover, and it might give a temporary fix but you may need the fuel injector pump with the new pmd sensor and everything thats what my truck was doing and I plan on having that fixed when I get the money too lol
Our 2005 GMC 1 ton diesel dually has the problem of the power dying, but not shutting down completely. We will be driving along and it is like someone shut down half the injectors! Very scary when on the highway with 18 wheelers. It has had several new fuel filters, a new air cleaner. Now if you go over 63 miles per hour it will lose power. Sometimes it will just chug (literally) along. I am very familiar with the emergency signals on this thing! If you stop and wait a little while, turn it back on, it may be ok. The engine light will come one. Thanks, Nay