Wet Weather Rough Idle

[petern4]

First hello to all you helpful and friendly folks on this forum. The spirit of the internet is alive and well.
I have a '96 3.8 Windstar.
1. Runs well, reasonable mileage.
2. Intermittently if I stop (engine off) after a short trip (15-20 min) restart is very rough, like a cylinder is missing, chugging. Rev a bit and everything is fine. But this is not all the time. Does not seem to be weather related.
3. Rainy weather, enough so there is significant water on the roads and it will chug enough that it will try to stall.
4. In this case the engine light will come on (code 1443). If the weather is dry for a period of time (month or more) the light will go out. If the weather again turns wet the light will come on but the performance does not seem to alter as long as there is not a significant amount of standing water on the roads.
5. Inspected vacuum hoses, replaced PCV valves and rear PVC to Crankcase ventilation tube. No change. Inspection shows no other obvious problems with hoses but I have not inspected for clogging, largely because it runs fine except in wet weather.
6. Am I wrong to think moisture is getting in somewhere?
7. I am thinking I will take a look at the MAF sensor and see if it is working correctly, p1443 says the VMV (which I presume is the same as the Purge Control Selonoid, somebody please correct me if I am wrong) but that doesn't seem right with symptoms as they are.

Well that is the problem, any thoughts would be most welcome.

[ama4ace]

I would suggest you pull a couple of spark plugs and check them for moisture. I had a similar problem and after 2 weeks of testing everything I could, I decided to pull the plugs I had installed 1 month earlier and found they were wet. Dried them up and everything was back to normal, (whatever that is with a windstar)? Water was geting in under the weather strip by the cowl and into the rear plugs. Just a suggestion. Could be the same thing...GOOD LUCK!

[Headnsouth]

P1443 Evaporative Emission Control System - Vacuum System - Purge Control Solenoid or Purge Control Valve fault

Rough idle in the wet weather might be plug wires/distributor cap