A vac leak simply means you have a hose somewhere with a hole in it that needs replaced. An engine generates vacuum so unmetered air will enter any hole where its not supposed to and lean out the mixture. The vacum is used to operate some things like brake booster etc but those hoses must be airtight
Find the leak, and fix the cause.
First you have to locate the source of the vacuum leak then you can determine what steps to take to stop the leak. Determine the source and re-post your question with more info.
I am having a stalling problem and I heard it can be the cause of a vacuum leak and if that is true how can i fix it and where is it at?
Need to know the location of the vacuum leak in order to answer this.
fix the leak
Get a new whip!
First you have to locate the source of the vacuum leak, then determine the next step how to repair it.
You need to find and repair the vacuum leak.
To fix a vacuum leak in a Dodge Ram, first, identify the source of the leak by inspecting vacuum hoses, intake manifold gaskets, and any other connections for cracks or loose fittings. You can use a smoke machine or spray soapy water around suspected areas to detect escaping air. Once located, replace damaged hoses or gaskets, and ensure all connections are tight. Finally, reset the engine's computer if necessary and check for any error codes.
Look for a vacuum leak.
This is an excellent article on how to replace the inner tie rod bushings, which are a common problem. http://www.allpar.com/fix/intrepid-steering.html
P0171 = System too Lean (Bank 1). I would start by looking for a vacuum leak under the hood.