OK now I have a P1443 code and my book only goes up to P0999 or somthing like that. does anyone know what the heck P1443 is???? STUPID Pocket Scanner!

---

It's an evaporative emissions dtc. To cure it, replace the canister purge valve and the flow sensor next to it. It should be located near the rear of the engine compartment on the pass side ona Mustang.
-----
One log says that the gas cap being lose (not screwed on tight) is the most common cause for this Check Engine light.
-----
The purge flow sensor is being tripped.

Could be the sensor or purge control valve, but the first place I would check is the gas cap seal.

Other possibilities:

EVAP system lines/hoses (check for proper connections, damage or blockage)

Loose fuel vapor hose/tube connections to the EVAP system components.

The vacuum line from the input vacuum port to the intake manifold on the EVAP canister purge valve (the control vacuum solenoid part of the valve) is removed.

Blocked vacuum hose between the EVAP canister purge valve solenoid and the engine intake manifold.

Damaged fuel tank or fuel filler pipe.