I have a 2007 Windstar with a 4.2l engine. It is making a popping noise in the intake manifold and it will shut down while driving like you turned the key off. I have replaced the air filter, the fuel filter, spark plugs and 1 coil. I have also cleaned the fuel injectors. If it matters, when I unplug the IAAC, it makes no change at idle. HELP, I am my wits end. Thank you in advance.

 

do you have a check engine light on?

 

No CEL but did have an active #3 misfire (prior to replacing the coil and plugs),

 

This is a list of possible cause for random misfire. You still can use it to chase down the #3 misfire:

A code P0300 may mean that one or more of the following has happened: Faulty spark plugs or wires
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector(s)
Burned exhaust valve
Faulty catalytic converter(s)
Stuck/blocked EGR valve / passages
Faulty camshaft position sensor
Defective computer
Faulty cam shaft synchronizer