P1506 1998 f150 4.2 engine miss fire when I crank it up. it wants to cut off when I come to a stop.

Question

Truck idling a little high. First crank it up and sound like a miss fire. When I come to a stop sometime. Sound like it going to shut off.

Answer 1

P1506 Idle Air Control (IAV) valve

What you have is more of a lean misfire condition that code P1506. Rupture PCV hose or even a disconnected vacuum hose will cause this condition. check and listed for any vacuum leaks especially at the intake plenum.