If you read in your owner's manual it will tell you the proper way to start your 12V. It's normal to have to depress the fuel pedal for about 30 seconds until the truck can hold it's idle.

You can fix this buy crank the injection pump a bit(this is what i did with mine) to bring up your idle to about 900 rpms. all you need is a 10mm wrench and about 10 seconds of your time, if you know what your doing.

Since I brought up mine, there's no need to depress the pedal, just hit the starter and she fires right up.

Here in Canada when it hits -20 you should cicle your glow plugs 2 times, and then start the truck.

Corbin