Nice good to see you back ya probably not MAP. Ok the diag for p1519 and
p0505 are about 30 steps of diag so lets just talk how the IAC (idle air control valve) works.

This is out of the book::::

Idle Control System Diagram
The idle speed of the engine is controlled by the idle air control (IAC) valve:

After the engine starts, the IAC valve opens for a certain amount of time. The amount of air is increased to raise the idle speed.

When the engine coolant temperature is low, the IAC valve is opened to obtain the proper fast idle speed. The amount of bypassed air is thus controlled in relation to engine coolant temperature.

Idle Air Control (IAC) Valve
To maintain proper idle speed, the IAC valve changes the amount of air bypassing the throttle body in response to an electrical signal from the PCM.

From me::::

Its a valve that controls the idle by bypassing air around the throttle plate. If the engine needs more rpm it opens a little if the engine needs less rpm it closes a little. Now we are talking 30rpms so you never feel this. If you look into your throttle body you will see an intake for the iac, turn the throttle you will see an exhaust port for the iac after the throttle plate. Now the iac has the capability of changing the idle from about 600rpms to about 1200rpms. So if it is malfunctioning it will kill your idle.

That said look at my pics.

Lets start with the electrical part of the iac (3 wires) the Yellow/Black should have 12volts with the key on connector pluged in. The Black should have less then .1 volts key on connector pluged in or connector un pluged 0 ohms good continuity to ground.

Get back with me. Safe bet p1129,p1519 and p0505 are all caused by a bad IAC but still lets diag to be shure.