My engine is hard starting

Good morning

From your description and the key is putting the fuel pedal to the floor, it sounds like it is flooded. by putting the pedal to the floor, it goes into clear flood mode.

This indicates an injector may not be sealing when the engine is turned off. that will allow fuel into the intake system.

if you can check the fuel pressure with a gauge, there is a port on the fuel rail, you can monitor the pressure. let the truck get hot and then turn it off. watch the pressure and see if it drops off.

These guides can help us fix it.

https://www.2carpros.com/articles/engine-cranks-excessively-before-starting

and

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Roy

Has the check engine light come on? It sounds like a temp sensor, but I can't be sure without the code.

Let me know.

The engine temp sensor. It tells the computer what the ambient temp is as well as the coolant temp sensor. With that information, the computer determines how rich to make the fuel mixture to start the engine and keep it running. If the temp sensor tells the computer it is -40°F outside, it will dump fuel to start and maintain the engine.

Let me know if you have other questions.
Joe

Check for fuel leaking into the vacuum hose to the fuel pressure regulator.

It sounds like low fuel pressure. What I need you to do is check fuel pump pressure. Here is a how to:

https://www.2carpros.com/how_to/how_to_check_fuel_pressure.htm

Pay special attention to fuel pressure drop off. THat is when you shut the key. Does the system hold pressure or does it drop quickly?

Let me know.

Joe

Hi and thanks for using 2CarPros.com.

Since you are getting a rich code, the first thing I would check is the coolant temperature sensor. This sensor tells the computer how rich or lean to make the fuel mixture. What you need to do is this. Get a live scanner. With the engine cold, scan through until you come to the coolant temperature sensor (CTS). The CTS should be telling the computer the coolant is about the same temperature and ambient temperatures. If it tells the computer it is -40 degrees F (that is an extreme) the computer will react by providing a rich fuel mixture for the vehicle. Thus, it will be hard to start, run poorly. I attached a picture of the sensor location if you find that is the problem.

Next, if that is fine, you need to check fuel pump pressure. If there is a faulty fuel pressure regulator, it will cause the same issues. Here are directions for checking pressure and the regulator:

Fuel pressure should be: Key On Engine Off 60 - 66 psi

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Okay, one last thing. If the fuel pressure is good, then I question if there is a leaky fuel injector.

If the check engine light is on and this information does not help, let me know all the codes which are found.

Take care,
Joe

Sounds like a plan. Let me know what you find.

Take care,
Joe

HAs it ever given any codes? (Check engine light) What brand fuel pump was used? I have installed customers aftermarket pumps just to take them right back out for low pressure/flow

I would look at the fuel pressure regulator again. Its simple to check. Just remove the vacuum line and see if gas is present. If it is or the hose is soft. Replace the regulator again.