Hard to start when cold, starts when warmed up

Here's some FYI on your situation. When you turn the switch on, all sensors are activated. One sensor is the cold start switch/temperature sending unit. When working properly, the sensor will send a pulse to the computer telling it to put the engine into cold start mode. Once this is done, a bit more fuel is added to the normal amount to the cylinders and the throttle is advanced slightly making the engine idle a bit faster for the extra fuel coming in. The engine is running to warm-up and the sensor then tells the computer to set the engine back to normal run mode. Once the engine is warm, the sensor is not being used for cold start mode. It will start right up and run smoothly. Now, since your truck is hard to start when cold, first thing you should check is the temperature sending unit wire connection first. if that connection is good, replace the temperature sending unit/sensor, and you'll be good to go. That's a simple repair that must be done when it gets hard to start when cold.

Think about how the vehicle is acting. Starts fine when cold, hard to start when warm. In these computer operated systems, the computer runs everything. Starts fine when cold: the computer has the engine in cold start mode putting more fuel in till it warms up. Temperature sending unit in the manifold sends a message to the computer telling it to stop the cold start mode and it stops dumping excess fuel into the cylinders and it runs fine. IF, mind you, IF the temperature sending unit is faulty, it's not telling the computer to stop the cold start mode and is flooding the engine with fuel cause it's sill in cold start mode. This is my take away on your situation and the temp sending unit is something to check to be sure it's functional. Check it out. I hope this WAS the answer to your problem my friend. It's typical. Luck to'ya Bro.

How to Start a Car in Freezing Cold Winter Weather

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wikiHowFreezing cold weather can take a toll on car batteries. ... It's much more difficult to start a cold car with a mostly-empty tank, so do yourself a favor and gas up ...

Why is it so hard to start a car in the winter? - HowStuffWorks

auto.howstuffworks.com/car-driving-safety/.../start-car-in-winter.htm

To start a car in winter, your engine has to work extra hard. Learn the top 3 reasons your car is hard to start in cold winter weather.

Debunking 5 Cold-Weather Car Myths - Popular Mechanics

it could be the starter, they can be affected by heat from being near exhaust components, or it could be the starter solenoid... also bad ignition timing could cause that

replace you battery

Have you checked base fuel pressure with a gauge before and after cranking the engine ?

Need year/make/model/mileage of vehicle to provide a more specific set of troubleshooting steps.

When was the last tune up? Hard starts when cold are usually caused by fouled spark plugs, worn plug wires, or weak ignition coils. Fuel systems are not as effected by temperature changes as the ignition components.

Kinda sounds like the ECM or "start mixture" control module is faulty or is getting a bad input from a sensor. For example, it man not be getting a proper temperature sense from the exhaust manifold or the intake manifold water temp sensor. So, every start seems like a cold start....

If your cold start is on a "cold" engine - fine. If your cold start is on a "warm" engine - problem. Mixture is too rich for a warm engine.

Again, could be sensor sending a bad temp signal... or the control module not responding to the signal.

A bit too complicated a problem to exactly troubleshoot via long distance... but you now have a starting point.... -Jim

egr may be stuck

Check fuel pressure, and regulator. A leaking regulator gives a warm engine more fuel [ it does not like it] a cold motor does. same as a flooded motor. Good luck