If your vehicle is disabled and you are considering walking back to get help, keep this in mind. Unless you are 100% sure of the route to take and know that it is safe to do so, leaving your vehicle could do more harm than good. It may be easier for search and rescue personnel to find a vehicle in the wilderness than it is one person.
Can you contact someone via cell phone or radio? do you have a CB?
Leaving your vehicle means leaving the security of your vehicle along with the emergency supplies that you have packed in the vehicle. If you do decide to leave, be sure to leave identifying marks that indicate your direction and travel. If you have a pen or pencil and paper, you can leave a note that says something similar to “at 3:23 pm on Nov 21st, I left on foot, heading in the direction of 232 degrees in an attempt to reach the town of Smithville which is about 5 miles away”. You can also leave other markings to indicate your travel such as sticks or rocks assembled in the shape of an arrow pointing in your direction of travel. This will help any search and rescue personnel in finding you quicker by knowing which direction you were heading should an emergency arise.
If you left a plan with someone you trust and it is not a medical emergency and you are prepared to sit tight, it may be a better decision to stay with the vehicle and wait for help to arrive. If you plan on running your engine while you are in the vehicle, you must be aware of the hazards of carbon monoxide.