Try a new fuel filter. If not that, replace plugs and plug wires. It's called a tune-up.
Either you need a tune-up, or your injectors are dirty.
i think it could be your FUEL PRESSURE REGULATOR. ours did that too
ford focus stalling at idle but not cutting off the check engine light is on please help so i dont get rip off thanks
throttle body or idle air control value
vaccum leak
there is an idle control on these cars, could also be a problem with your intake, and idle. that's what was wrong with my 2000 focus. i lowered the idle, and changed the air filter.
p1506 is an IAC (Idle Air Control) error code that comes on when your on-board computer senses an undesired Idle RPM.
PO 1507 is Idle Air Control System Underspeed
your electric radiator fan might not be working,check fan fuses
It is right next to the air filter
The resolution to the problem above was two broken motor mounts and hairline crack in a vacuum hose.
Look for a vacuum blockage or a vacuum leak.