[Brando]

The plug on the side of the air flow sensor (yeah, called an afs, when it's not?) is what turns the fuel-pump relay in the cab, thus turning on the fuel pump to pressurize the system.

Let's do a little testing. With the plug hooked up, and the AFS hooked up and everything put together, take the air filter portion off. You should then be able to reach inside the airbox and feel the bottom side of that plate. Turn the ignition on, and lift up slightly. You should feel pressure pushing the plate down against your fingers. You should also hear a "click" noise and hear fuel running through the lines. Don't do this too long, though, as you're pouring fuel into the engine by doing this.

And please, only connect the right connectors to their plugs!!! They do different things on the engine components and if you swap them around your chances for success plummet off the bottom of the chart.

If you're having hot/cold start issues, look at diognosing these things:

Cold-Start Valve, if you've swapped those connectors around in the engine compartment, chances are you have the wrong one going to the cold-start valve. This thing drops some extra fuel in (like the AAV allows more air) but only for about 3-5 seconds so it idles properly. Follow the testing procedure to see if yours is good or bad. Also clean it.

Auxilary Air Valve (mine was bad), between the injector lines and intake manifold. You'll see from the black air intake boot near the manifold a small tube that goes to the AAV. It has the black connector on the back. The AAV is a heat-sensative valve. As the ambient air temperature reaches a certain level, a disc with a 'window' turns and closes. When it's colder, it opens to allow more air. Take it off and test it with an Ohm meter. Should have i think 3.5 Ohms. If it reads -1 or open it's bad. If it reads fine electrically, put it in a plastic bag and leave it in the freezer for 15 minutes. Take it out and look through the hole, it should be wide open. If not, this be your culprit (or one of them).

Warm-up Regulator, Another common culprit for hot/cold start problems. Read the manual on testing this, as it's a real PITA to get on and off. Pretty much it's a sensor that if the coolant temp is at or above a certain level, it disables the Cold start valve and also manages fuel pressure. If there's an air bubble in the coolant by this thing, bleed the coolant system.

That's usually about all to consider with hot/cold start issues. I hope i didnt forget anything.