It's a 2004 with a 5.7L Hemi (w/ 4WD). The main problem is that every time it rains, the engine starts running really rough, and a heavy rain will cause the engine to completely stall out/not start. As soon as the rain dies down, engine can start again (I don't need to wait for things to dry off, just for rain to stop). I've had the plugs, plug-wires, etc. all replaced to no avail. The engine light has been on for a while, but if it's throwing a code, that didn't help the dealerships fix it (I thought maybe an O2 sensor, but would imagine if that's what it was, it would have been fixed the first time in the shop).