Chrysler Repair: 1996 Plymouth Neon shuts down!, plymouth neon, crank sensor

Question
Hello,
  I have a 1996 Plymouth neon. I just replaced the 2.0 SOHC with a 2000 2.0 SOHC. I made sure all sensors remained compadible to the 1996 computer model and it ran beautifully for a week, with no issues. After the week of running great, I was driving the car and it died unexpectedly;while under power. When attempting to restart the car, I noticed the car shaking as if it was hard starting or a little out of time. Turning the key off and waiting roughly 30 seconds,the car re-started and ran beautifully again;until put in gear and under power. I have noticed that every time I start the car, it will idle all day long and run as smooth as a baby's rear end, but as soon as; the engine gets warm, I put the car in drive, and give the car gas, the car dies and repeats the behavior of the first time it stalled. I have checked the timing and it is dead on. I have checked the codes and found a few issues to be corrected. I corrected all issues and there was no longer any code to read; the car idled beautifully. I took the car out for a test drive and it died again (this has happened many times now). The code I now get is 0140, which tells me the down-stream O2 sensor is staying centered: What does that mean? Is it possible for an O2 sensor to stall the car, when the car has the load of being in gear and accelerating only? I have given thought to a cam sensor or crank sensor, but those are not the codes I get, and the car idles as nothing is wrong with it. I have also given thought and not ruled out replacing the computer. I have replaced the fuel pump and filter, tested the fuel pressure at the maifold which is (49). I have replaced the (cat) and muffler due to the last engine getting very hot many times. I have also changed O2 sensors, but some thing is telling the computer to shut the car down and I can't find it. When the car dies, it is as if the car has lost all power if I had completely run out of gas, but then re-starts 30 seconds later. Can you help or do you have any ideas? I have worked on this crazy problem for more then a week now and I am running out of where to look. Again the only code I get currently is the 0140. Thank you and I look forward to hearing back from you.

Answer
Hi George,
I would check the wiring from the downstream sensor to the pcm.
The harness for the '96 model show the black wire should be grounded to a ground at the top left radiator closure panel, dark green/orange is a common output of 12v from the autoshutdown relay that also will be found at the upstream sensor and pin 6 of the pcm C2 plug, black light blue is the reference ground for the sensor which should be connected to pin 43 of the C1 pcm plug, and the tan/white is the signal and it should be connected to pin 51 of the C1 plug. I suspect one of those wires is "open" if you have indeed relaced the sensor in question.
Please let me know. Sure, an O2 sensor issue can cause your performance issue. Thanks much for the very complete history.
Roland

I apologize it has taken so long to get back to you, and being that other people are having this issue as well, here is what I have found out!
The O2 sensor was only a small portion of the problem I was having and the code I received was only masking the real problem. The Camshaft sensor was the problem being masked. The car would idol just fine, and very smoothly and controlled, but when demand was placed on the engine to perform (put in drive or reverse, and fuel pedal pressed down) the camshaft sensor would cut out or fail, causing the symptoms and confusion I explained earlier.
I replaced the camshaft sensor, which required me to remove four bolts and unplug wire harness from the camshaft sensor. I replaced the camshaft sensor, and the camshaft issue has gone away. Replacing the camshaft sensor is not difficult in my opinion, but a little difficult to get to the bottom two bolts. Doing it your self worked great for me, but it is not for everyone. In the case that it is not your thing, take it to a certified mechanic. It should not take them very long to replace.
Thank you for your repair answer. I checked the wires you had mentioned and I am still tracing the O2 sensor issue, but your advice has given me a solid direction! Thanks for that! I don't have a scope and this makes the process time consuming. I have learned more about our 1996 neon, then I thought I would ever want to know.
My advice to all would be to document exactly what the vehicle is doing, and the problem you are having could be very random in the problems timing of things, but don't give up! Use your resources and research the symptoms before replacing parts. I really believe throwing parts at the problem, in hopes a solution will be the result, is not the answer, just costly. Thanks for the advice.

Hi George,
Many thanks for the report, which I have formally added to the original q and a so others might learn from you experience. Nice going on that cam sensor. The crank sets the timing, but the cam sets the injector locations to pulse, so if that goes bad there is poor timing of the fuel injection.
Roland