Ok , That EGR valve btw has another inbuilt feature , the mechanical side of it (the valve bit) is actuated by the vacuum BUT that valve "also" if not seating properly will let exhaust gas's back into the inlet manifold which could be the symptom you have , and it would be real noticeable at around idle .

One has to remove it to check it out , sucking on the actual vacuum canister should have no leaks (i think it throws a code anyway) , and sucking/blowing where it bolts on to the manifold should have NO pass through ie: blocked off , maybe worth a try .
good luck .

 

Agree with ipn. Didn’t see PCV hose on your list of parts. Might check if it’s sucking shut or leaking. May be difficult to see if it has the outer “foam” cover. Also seen them go bad on Ford V8s a few times.

 

Did you ever get this fixed? I'm having the same issue with the same year model.
Since you've replaced all that stuff, the only thing I can think of is the engine coolant temperature (ECT) sensor. A cold engine requires a bit more fuel. A faulty sensor might not send the correct signal out. And this symptom seems to only happen to a cold engine.

 

Coolant temp was as expected per my scan tool. I replaced everything mentioned and it doesn't stall anymore, but maybe once a month it will idle low at traffic light or when stopped. There is probably a small leak somewhere, but isn't causing enough of a problem to warrant tracking it down and fixing it until it gets worse.

 

The stalling eventually got worse and I purchased a smoke machine to look for any vacuum leaks (and fuel vapor leaks). Several leaks were detected and fixed (old dry rotted hoses that broke and fell off). Stalling issue now 100% resolved.

 

Two years to resolve , must be a new record?

Well it’s nice to read a final solution and resolve.

 

Plastic intake manifold?

Had this exact problem on a Corolla. A small crack would open when cold then close when hot. Our scanner could read manifold pressure and that's how we found it. In the old days, I've seen people use smoke from an incense to track down vacuum leaks...lol! I would proceed assuming a vacuum leak and try to find it, or not.

Edit: If you want to make your own repairs, invest in a good scan tool. A couple hundred dollars is well worth the money to track down issues in minutes instead of hours of throwing parts at it. If you have friends that also DIY their repairs, pool your money and buy one good unit to share.

 

Yes and never replace a part based on a trouble code without first verifying it to be failing or failed. Doing so often creates more additional problem adding to the yet unresolved original problem.