got a few problems with my girl's new car

[turbobuickman]

She drives a 2000 plymouth neon. Every so often the thing sputters and almost stalls while idling (I can see the revs drop on the guage to 500 or less). I guess the best way to explain it would be It acts like it was running out of gas. Seems to happen more when the engine is cold, the car is stopped but in gear and when the a/c is on. Other than that it runs as good as I imagine a plymouth neon would brand new. Can anyone help me narrow down the possble causes?
Also, her trunk and rear floor pans filled up with water after the monsoon last week in MA, a dealer said they tend to spring a leak by the tailights, before I start tearing the car apart...has anyone ever run accross this?

Thanks

 

[John Larkin]

The water leak at the taillights has been known to happen. Remove taillight, silicone around any holes there and reinstall ensuring a seal was created. Reminds me of my old Grand Am that leaked at the cowl; never found that leak, had to drill a hole to let the water run back out.

Stalling might only be dirty throttle body, IAC, etc. A can of Gumout sprayed through everything (except the MAF if it has one) is a cheap test.

 

[IrvJr]

There was a recall on headgaskets for those cars. I dont remember what years though, my bro and one of wifeys friends got them done at the dealership.