02 GC periodically stalls at lights with cold engine

My wife drives a 2002 Grand Caravan Sport 3.3l with about 160k miles on it. In the past month or so my wife has told me it has started to die when starting up at stop lights. It's only happened once when I was present so I mainly have to go on my wife's description of the problem.

It only dies when the engine has not reached operating temperature, so first thing in the morning or after it's sat for an extended period. The usual light that it dies at is about 1 mile from our house. It does not die on every cold start, and we haven't found any pattern to match things up to (e.g. cooler mornings, warmer weather, low or high humidity, raining, etc). As far as I know, it has never died while the vehicle was already moving. Approaching a stop light it slows down normally and idles smoothly. When the light turns green and the accelerator is pressed, the engine hesitates. At that point, it either stalls out, or quickly recovers and accelerates as expected. If it does stall, it will easily restart.

Plugs and wires were replaces early spring and fuel filter was replaces last fall. Air filter is about a year old and looks decent still. It was my in laws vehicle until about a year ago so I don't know the service history, but I would presume that everything else (o2, EGR, IAC, etc) is original from the factory.

There are no trouble codes set that I think would relate to this issue. There are two codes set relating to the EVAP system, but those have been present since early winter so I don't think that plays into things. It idles fine both cold and warm, so that would seem to point away from the IAC. Gas mileage is great, getting in excess of what the EPA rating is for both highway and city driving. If the EGR or O2 were bad, I would expect mileage to have suffered at least some. Plus the O2 doesn't come into play until after it's reached operating temperature i beleive.

I'm just not sure where to go from here...

I saw a service bulletin that talked about sag--hesitation. Said to replace the throttle position sensor. Don't know if that will fix the issue?

Ditto. TPS. You can test it using a multimeter. Look for dropouts as you move it. Heat it with a hair dryer before you start it up. See if the problem goes away.

I was looking into the EVAP codes that were set, looking for cracked lines and such and discovered the PCV valve was broke and had appeared broke for some time. The threaded portion had broke off in the valve cover. It took me having to remove the valve cover to extract the broken piece. While I'd love for that to fix both the EVAP codes and the hesitation, I doubt that's the full cause. It ran find though both last night on a test drive and a drive around this morning but only time will tell.

I'll remember the TPS sensor though if it does come back.

That could be the problem. It uses engine vacuum to operate. Essentially you had a vacuum leak. Low vacuum at idle will kill the engine.

Most of us, including me, take the PCV system for granted. Maybe we should all pay more attention to it. This is an excerpt from an article at machinerylubrication.com:
"The consequences of ignorance about PCV systems can also be costly. The system is simple. As a professional mechanic, almost every week I see a malfunctioning PCV system literally grinding an engine to bits. The rubber hoses and grommets that are part of the system can swell and loosen their connection to the other parts of the engine. The results depend upon where the integrity of the connection fails. If the connection is loose and sucking air into the line between the air filter housing and the valve covers or other intake point, raw unfiltered air is introduced to the crankcase. This can grind bearings, overload the oil filter capacity and in general, make a junk pile of the engine. Many of the prematurely worn out engines I have seen can trace their failures to a long-term malfunction of the PCV system.

If the connection fails on the other side between the PCV and the intake manifold, raw blow-by products spew into the atmosphere. The results are the terribly messy, oil and dust-coated engine compartments that many of us have seen, and the release into the atmosphere of many aggressive pollutants.

The ignorance and lack of attention to detail made my first wine experience my last. Don’t let the lack of knowledge and disregard for the simple PCV on your car cost you many miles of service from your modern-day combustion engine. Either you or your mechanic can inspect this entire system in just a few minutes. Hose, grommet or PCV replacements often cost less than $20. Do yourself and the environment a favor - check and/or repair this vital system this week."