The truck will not start when it gets 20 degrees when it is jumped it will start

Check wiring harness to temp sensor. Conduct a voltage test on sensor using a DVOM.

1. If you can jump start the truck to get it started but not start it with the current battery then you battery is most likely bad and needs to be replaced. (See 2 also).

The problem is the battery is most likely not producing the CCA (cold cranking amps) and CA (cranking amps) that it is supposed to and did when new .( These CCA/CA ratings are listed on the battery label.) In that event you will never be able to start the vehicle.

A basic voltmeter and basic load tester won't tell you if the battery is failing to produce the required CA / CCA to get the vehicle started. Both can indicate your battery is quite passable and OK until a CA/CCA tester is applied and will show the CA/CCA the battery is actually producing which in a failing battery will be well below spec.

2. You should also disconnect the battery cables and clean the battery terminals and cable clamps. If dirty you can get very poor current flow from the existing battery. As a first step check these connections and clean them and eliminate dirty terminals as the cause of your power issue before replacing the battery as suggested.

Hello, sounds like you have a weak battery, take to a service place and have them test your battery.

Weak connection between battery post and cable. Since the jumper cables bypass this, by clipping on the cable ends, the car will start with a jump. Takes less current to start a warm car than a cold one, hence it starts all day. I would look closely at the cable ends where they attach to the battery. Clean them until spotless with baking soda and water and terminal cleaner brush.

If this does not solve the problem, clean the chassis ground on the other end of the - battery cable and + cable where it connects to the starter.

Check your alternator output also. Battery should not be defective in 2 years.

Possible current drain when key is off. Put a voltmeter inline with the battery and check for draw. If you get more than a few millivolts something is on and drawing current. Glove box light maybe? Check by pulling fuses until you find the source of the draw.

Bad battery

on most newer cars there are covered terminals near the front of the car.. these covers say on them remove to acess terminals for jump start..

Maybe vacuum leak it loses when first starting

If your battery gauge went to zero whilst driving it sounds like your alternator stopped charging. Either the alternator itself failed or you chewed a fan belt. If you jump started it, and the battery light stays on or the gauge still reads zero then that would confirm the above.
Driving or running the car without alternator charge will simply run the battery to zero. it will be quite hard to even jump start after that.
Check for broken,lost belt and get it running again and watch the gauge/batt light. If its on, its not charging, if its off then you most likely have a battery going bad.

You probably have OIL that is TOO thick in the unit. During the winter use 10 weight oil. 20-30-40-50 is too thick for really low temps. Your Oil is probably like molasses right now.

Putting a BLOCK HEATER in the engine will heat the BLOCK, thin the oil and allow everthing to turn just great. Go to your local auto parts store, and they probably have one in stock, if you do not wait too long. This is common.

DO NOT HEAT ENGINE WITH HOT WATER, BLOW TORCH OR ANY OPEN FLAME.

Kindly,

Jim

time to have the injectors replace and calibrated by an accredited diesel specialist shop
indicates squirting and not atomizing