Chrysler Repair: neon 97 cranks, no start, no spark, crankshaft sensor, oxygen sensors


Question
QUESTION: i was driving the car and battery light came on the car did not die. i pulled over switched it off and started the car after 5mins it started fine the battery light swiched off as normal. it did not come back on.  
the next day it happened the same way and this time it was raining the car died. it gave code 12112155 after 5-10mins it started again and moved ok , then it would die  and start  again at simillar intervals. i got home and this morning it cranks , no start and no spark on plugs. what could be wrong

ANSWER: Just 'answering' to clear this question from the 'pool'.

---------- FOLLOW-UP ----------

QUESTION: your reply was dead on the target. changed the crankshaft sensor and one kick the car came to life.

i have another problem arising this time, the car starts moves but at random intervals it sort of feels like it jerks/stall and picks up again. at one time it felt like it was losing power and moved slow i didnt try to force it and it picked up. i changed the plugs it still does the split second jerk/stall sometimes 2,3 times in short space of time i got the following codes 12-21-47-55.  
i would appreciate your assistance

ANSWER: Hi Tony.
The 21 code means that one of the oxygen sensors is not changing its readings which means that it is either faulty or one of its four wires is broken. It doesn't specify which sensor, so if you can get a free code readout using a plug-in code reader for the 4-digit OBD-II code number that would help to localize the issue. Otherwise check both sensors for signs of wire breakage.
On the 47 that is saying the voltage output of the generator is not high enough so again watch the charging warning light for indication of that problem (it appears that the Neon does not have a voltage meter as such.
Either of those codes might cause a temporary loss of power, though the oxygen sensor is perhaps more likely.
Please "rate" my answer (see below).
Thanks,
Roland

---------- FOLLOW-UP ----------

QUESTION: hi

i drove the car last night and it was stall/jerk and occassionally sputter. stall  and then cruise as if gas lines suddenly openned up. got home and disconnected the battery and when i tried to start it it would not start. Roland i did the key trick and it gave me 12-54-55. this is a diffenent code than i got last week for oxygen sensor. could this be the cause of my problem all along and does it play a part in the oxygen sensor giving a check light

Answer
Hi Tony,
The 54 code is pointing at the camshaft position sensor and were it failing it could certainly cause stalling. I don't see a relationship to the oxygen sensor code as that is on the 12v supply while the cam sensor is a 5v supply item. But in any case if the 54 is valid then it would be reasonable to replace that.
Please 'rate' my answer (see below).
Thanks,
Roland