Chrysler Repair: 1997 Chr Cirrus 2.5L: dies, but no codes, lean mixture, mixture control

Question
My cirrus stalled while driving 2 weeks ago and since then has continued to do so.  It will crank the motor fine afterwards but may not start for up to 20 mins.  Autozone pulled the codes and we replaced the MAP Sensor which had black soot on it and smelled and tasted like diesel.  Even with replacing the sensor, it still has the same problem.  I have noticed that after it does restart, there is a strong smell of gas as if the motor was flooded.  There is some sputter before the stall, but it has just died as well.  I just pulled the code manually and got a 12, battery code, nothing else.  Any help is appreciated.

Answer
Hi Ken,
Without any specific codes pertaining to mixture control it is very difficult to identify a cause for an overly rich mixture (or perhaps a too lean mixture that won't ignite, which appears rich). The failure to restart and then after 20 minutes to restart, on its face, would indicate a failure of one of the spark/injector related sensors. One of those two may be in the process of failing but is still putting out sufficient pulsing to not set a fault code. So you may just have to bear with it until it gets worse and you get a code.
About the only mixture-related part that might be failing and cause a temporary no start would be the egr valve. You might want to inspect that for freedom of movement of the valve stem. It it hangs up ajar it can dilute the mixture too much to allow idle. It is located in a pipe that runs from the front bank exhaust manifold back to the intake area. You will find that it has a flange in between its two parts and inside the flange you will see the valve stem that has a circumferential slot. Insert a screwdriver tip in the slot and move the stem back and forth. Internal spring action will try to shut the valve. Make sure that it does move the stem to the full extent of its motion in that direction reliably (closed position). If it seems to be slow or sticking then spray the valve stem with WD-40 at the place where it enters the valve body (the part bolted into the pipe).
You might want to pull the three easily accessible spark plugs (2,4,6) at the time of a stall to see if all are equally wet. If not, then that would indicate a faulty injector.
Those are my best suggestions at this point.
Roland