QuestionQUESTION: Roland, my Dodge Will not start it turns over well getting fuel the codes that show up are 21,12,41,43,51,53,62
the car was running fine when before it was parked there
was no warning before hand my wife was driving it at the time she did tell me that the fuel light did come on she drove about 1/4 mile with it on and there was no low fuel warning bell before that she then parked it she told me the next day I then tried to start it that is when I saw all the codes I did put a gallon of gas in it but still
wont start Help!!!
ANSWER: Hi Billy,
That is quite a string of codes! The 12 is often there if for any reason the battery was disconnected in the past 50-100 key on-off cycles.
21 and 51 are about the oxygen sensor on the exhaust manifold either reading toward a lean mixture, or not responding any longer. That probably indicates a failed sensor or failed wiring as those devices are fragile at the tip where the 4 wires attach.
41 says the alternator is not responding in terms of controlling the voltage output that the engine computer is telling it to do resulting in probably a red charging light (could that be what your wife observed?).
The 43 says that one or more of the primary coils of the spark coil pack are not responding as the engine controller would expect them to, which implies you may have lost or weak spark on 2 or more spark plugs.
The 53 code says there is something wrong with the engine controller itself, and the 62 (is undefined, could it be 63?) if it is a 63 corroborates the 53 tells about an inability to communicate internally by the controller.
It is hard to decide which of these to address first, but my inclination is to suspect the engine controller has gone bad. Probably the most economical approach would be to find a used one at a wrecking yard, one that was installed on a '91 Dynasty or Chrysler New Yorker with the same engine as in yours. It is a simple plug and play exchange and if you disconnect the battery before and after installing it and then see if it will start, and if not read the codes again we can go from there.
You may need to add another gallon of gas to the tank in order to get a better prime of the pump. And also listen to learn if the fuel pump hums for about a second when you turn the key to the run position, which it does normally.
I'll await your progress report with interest.
Roland
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QUESTION: Roland,I am not sure of the 63 code I could have missed
one while counting the flashes, I replaced the computer
several days ago with no luck and now I don't have any codes
except 12 and 55 I thought you had to have the car running to get codes to store in the computer I will check the o2 sensorI dont think it have ever been changed will this not let the engine start thanks
ANSWER: Hi Billy,
You won't get the oxygen sensor codes until you start the engine and have it warmed up to warm temperatures. The sensor has nothing to do with starting because it doesn't come into play until the engine is warmed up. The alternator code too may not reset for a while. I think if the spark coil were the problem that it would set a code without having the engine start. But I would not assume the coil pack/circuitry is OK.
I would get some more gas in the tank if it really ran down quite low. And also I would remove the spark plug caps, one at a time on the three plugs that are easily accesible, put the tip of a screwdriver with a plastic handle into the cap so the tip touches the wire wire in the bottom of the cap, hold the cap and driver with two hands and position the metal shaft of the driver 1/4" from the cylinder head, and then have a helper crank the engine for 5 seconds and observe whether you get a good spark for 5 full seconds of cranking. Test each of the 3 plugs.
If you spark and fuel then you should get it to start again.
Roland
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QUESTION: Thanks Roland for the help car is running well I will check
for codes and get back with you don't know why there was no
low fuel light before tank was empty fuel pump was replaced
over the summer and was working ok even the low fuel light and bell
Bill
AnswerHi Billy,
The fuel level sending unit in the tank provides a single signal to both the fuel gauge and the low fuel warning light, so if the gauge is accurate then the light bulb for the warning light may be "out". I don't recall there being a warning bell for low fuel, but perhaps there is on your car. I am glad to learn that it is running again. Was it putting in more fuel that did the trick?
Roland
