Rough idle when wet

Whenever it’s wet or damp out because of rainfall, my 2005 Dodge Caravan idles roughly for the first 3-5 minutes and sputters a bit when I take off and then evenyually corrects itself. What is the cause of this?

Usually it is from bad ignition components - spark plug wires would be the first thing I’d look at.

You can easily learn some about it. Get a spritzer bottle of water and pick a dry day. Start the car, open the hood and start misting things. You can variably shield things to pinpoint the location.

You might even try a dark garage or at night when doing that test.  If you get sparks, replace it.

Specfically, Which Engine Is In This Vehicle ?

If your 2005 Caravan has a 3.3L (with sales code EGA or EGM) or the 3.8L (with sales code EGH) engine , built on or before April 2, 2004 (MDH 0402XX) and possibly The Check Engine Light’s on and it’s throwing codes PO300 MULTIPLE CYLINDER MISFIRE, PO301 CYLINDER #1 MISFIRE, PO302 CYLINDER #2 MISFIRE, PO303 CYLINDER #3 MISFIRE, PO304 CYLINDER #4 MISFIRE, PO305 CYLINDER #5 MISFIRE, and PO306 CYLINDER #6 MISFIRE then there may be a remedy.

After thoroughly diagnosing (using a Scan Tool with TechConnect) the vehicles (while under new car warranty) with these specifications and symptoms Chysrler dealers were replacing the spark plugs and ignition wires and if necessary reprogramming the Powertrain Control Module with new software in 2004 and 2005 Caravans and Town & Countries.

I am guessing that the plugs and wires are “revised parts,” but maybe not. Check with a dealer.

Do you know if you’ve had this done ? It’s a long-shot that this applies to your situation, but Chrysler’s got a four-page bulletin on this topic and may help you identify your engine.

I’m curious if your’s is an “early” 2005. What is the Date Of Manufacture on a tag on the driver’s door / door jam ? I believe the 2005 Model-Year begins July or August, 2004.