Chrysler Repair: rough idle, neon sxt, exhaust gas recirculation valve

Question
i just purchased a 2004 neon sxt with auto and 12000 absolutly pristine miles. car looks like it came right off the assembly line. when i stop at a light it sometimes goes to 600 rpm from 800. i just tap the gas and it will go back to 800 and stay there. took it to dealer  who flashed the computer as the car is still under warranty. no change. i put in new oem plugs air filter and msd wires; no change. from various sources i was told that it could be power steering pressure switch; carbon build up from lack of use; or thats just the way neons run. dealor has been of no help. i would tend to think that dodge doesnt build cars this way and then tell you thats the way this particular car runs! car otherwise runs perfectly smooth; just a funny and rough idle sometimes. any thoughts?

Answer
Hi Ronald,
Stumbling when you come to a stop is often associated with a too lean mixture which results when the exhaust gas recirculation valve is hanging up slightly ajar. It is open when you are cruising, but has to close at idle.  So I would take a look at that possibility. Depending upon the design of the egr it may have an exposed valve stem and if so you could try moving it back and forth using the tip of a screwdriver in the slot of the stem, and an internal spring should close it tight. If it seems sticky then spray some WD-40 on the stem where it enters the body of the valve.
Other than that, you might keep checking for fault codes which you can get read out for free at many Autozone parts stores. Something that is too marginal may mature to a set code which will then tell you where to look.
Roland