What's the p0171 code Chevy Colorado?

The P0171 code on a Chevy Colorado is a catch all code that can be shown for a number of different reasons. The most common cause is a problem with one of the vacuum lines or a cracked EVAP canister. To check for a vacuum leak the first thing to do is visually look at all of the rubber lines running to and from the engine and its components. Check to see if any of them have come loose or if they have any obvious cracks or tears. If they all look good You will need to check for leaks by either listening for a light hissing sound, which is not very easy with the truck running, or have it tested by a service center.