My 2000 taurus surges acts like a vacuum leak i was told it might be the idle air control

large vacuum leak at rear hose from pcv valve

Check for a vacuum leak. This can cause a higher than normal idle. It can also cause a surge since the idle air control tries to adjust the amount of air required to idle.

The code is for the idle air control valve which controls idle speed.
The problem could be a faulty control valve, or a vac leak which is letting in air to the intake and bypassing the control valve.

P1506 Idle Air Control
Overspeed Error

IAC Valve--Bad
Vacuum Leaks
IAC Stuck Open
Failed EAVP System

Disconnect the valve--if little
or no change in RPM,then
Valve is stuck or bad

You may have been told correctly,check it out.

If it just dies, sounds like the Idle Air Control Valve. If it surges and runs rough, sounds like a vacuume leak, especially if it is the DOHC 3.0L engine, they have several vac hoses that go bad.

apply a light force to the gas pedal and start the car continuing to regulate the rpms with gas pedal if you can make the car idle with the gas pedal then you will probably need a new idle air control valve

ok a couple of things to try one is loosen the throttle cable so it has a little play in it and then you can check for vacume leaks using carb cleaner if rpms change you have a leak

you need to ck some basics you could have a vacuum leak which would hide during warm up but cause havoc when hot,the leak would cause high idle then your pcm would try to lower idle to spec thru use of idle control motor causing surging idle ,also fuel pressure needs to be checked while acting up,may be more cost effective to pay for an hour of diagnostic.

This could be a bad a/c compressor or compressor pulley bearing.Try removing the serpentine belt and turning the compressor by itself.The bearing should turn very easily,and the compressor itself should turn.If it is vety hard to turn,it is bad.