Chrysler Repair: neon 97: runs poorly when started, coolant temp, coolant level


Question
QUESTION: hi

iam baffled i took the neon for diagnostic test and everything came out ok. except coolant sensor which said out of range.  the car does start, moves but at some stage stalls/jerks and if the rpm is not above 1 then it loses power and almost stop. at the workshop the technician. says we need to check the timing and maybe change coil pack. he did the spark test and it came out fine.  
he tried removing the engine check light , but it wont go away even after trying to erase the only stored code . the fans come on i think regularly blow and turn off after 5mins not sure what the sensor might be picking up

ANSWER: Hi Tony,
I would change the coolant temp sensor as that sets the mixture based upon the engine temperature and if that were wrong then you will have a poor mixture. If I understand you correctly you do have start, and you do have spark. So if the only code is coolant temp sensor then change it. It is located near the thermostat housing on the top of the engine and has a 2-wire plug: tan/black and black/light blue. Then see if the code goes away and it runs better.
How is the level of coolant in the overflow bottle? It is possible that if the coolant level is low or there is air in the cooling system that the sensor will not read correctly, but again it is cheap and you can replaced it yourself.
Please rate my answer (see below). I would appreciate that very much.
Thanks,
Roland

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

QUESTION: the coolant is ok by the full mark. i have noticed it is slightly under full when the car is cold and when warmed up it rises to full level is that normal?  AGAIN The technician i saw mentioned that if the timing is slightly off the car might misfire is that accurate because when he put it at 2.5rpm there was a sound that sounded like a misfire and yet confusing thing is that when he tested the spark its like it was ok

Answer
You can't manipulate the timing as that is set automatically by the rotational semsors of the engine. Again, change the coolant sensor to get rid of that code. While doing that check the condition of the 2-wire harness as far as you can along its length to find any damage of the wiring.