Engine crank in cold morning but will not start?

2003 Ford Taurus:---

2002 ford taurus won't start at first crank in the morning.When I start my car in the morning, it crank but would not start. After two or three times it starts. I had a new fuel pump, new fuel pump module, new fuel filter, had the air flow cleaned out, still having the same problem.When I turn my key in the ignition, sometimes I don't hear the fuel pump kick in. Once I hear the fuel pump come on I know that it will start.

If the starter-motor turns the engine over, but it does not start, then get out, remove the gas-cap, and replace the gas-cap, and try again. Works for me! (relieves any vacuum in the gas-tank).

Try having your battery tested for CCA (cold cranking amps) If your CCA is 400 or lower you probably need new battery.

Mechanic suggested this  ...............

Remove the air filter housing from the throttle body, or if its mult-ported injection, remove the large air duct. Do this the night before. The next day, before cranking and having a spray can of carb. cleaner, spray a couple of shots of carb cleaner either into the large air duct, spray towards the engine, or if its single body injection, spray directly on to the throttle body.

Crank engine immediately, preferrably have some one else sitting in the car to start it after you spray.

If the car even tries to start, replace cold start relay.

OK,at last problem is solved.

In switching the relays, engine works just fine, maybe it was just a bad connection, no one will ever know.But mechanic pointed me in right direction.