I was thinking that someone's experience might help me with a strange problem. My 1995 Neon does a very annoying thing when it gets hot. After a variable time, I assume it depends upon the weather, after driving, when I come to a complete stop the engine starts to rattle and eventually dies. No problems while driving though. Same thing happens if I leave the engine idling for more than 30min or so. If I wait about 10min and I start again, the engine runs well for an extra 5-10min and then dies again. The PCM tells me that I have the "Oxigen sensor stuck at lean position" which makes perfectly sense with the behavior I get. I already replaced: spark plugs, ignition module, MAP+IAT sensors, oxigen sensors(both), IAC module and PCV valve. The only two things I am thinking of are the PCM and theTPS. I do not know though if the EGR subsistem could produce something like this. Otherwise the car is fine and I really like it. If anyone has any idea of what can cause such a demeanor it would be greatly appreciated.

I'm having similar problems with my 2000 dodge neon. Were you able to figure out what was wrong with it?

I did not have enough time to do nothing this weekend, but I am seriuosly thinking to replace anything left that has something to do with the temperature:
- Battery sensor, which informs the PCM about the environment's temperature.
- EGR subsistem, valve, transducer, solenoid & hoses-recirculating.
- Engine Coolant Temperature sensor.
If this works, I am done, otherwise I will just kiss this thing goodbye!

I think I'll take a stab at this.
On the other side of the circuit,
The O2 sensor shares a circuit with the other O2 sensor as well as:
ignition coil pack
generator
0.47 mF cap
all the injectors and the
noise supressor
downstream circuit of the auto shutdown relay.

Could be a bad ground but it sounds like fuel supply issue too.

Fuel pressure OK?
If ok I'd snoop around the injector side of the circuit.

On top of my other list of already replaced parts, I will add the whole EGR system and the battery temperature sensor. Still nothing! Dangerous test on highway, that I would not recommend to anyone.
But, researching again facts and combining some other advices I reached to this conclusion: FUEL PUMP. Fuel pump delivers below the prescribed pressure when the outside temperature is slightly above 70-75F. It is true, because whenever I drove the car UNDER this limit I had no problem, ever! So, I replaced the fuel pump with a recovered one from a scrapyard. A new one would cost you a least an arm and a leg. Now I am testing it again, hopefully this will fix the problem. I will let you know about my success! Wish me luck!