Chrysler Repair: Cirrus 95 rpm idle probs, air fuel mixture, coolant temp

Question
QUESTION: dear mr. finston,

I wrote you 10 days ago about my car and got a reply the next day for which I thank you (aug. 26, 2008).....I did what you suggested about the blinking of check engine....at first nothing.....then more than 2 times, it gave me the same blinking sequence which is: 1,2,4,4,2,2,5,5......meanwhile, I am having my mechanic clean the throttle throat butterfly plate and the air passageway.......the readout of the diagnosis was no commun.....then today it gave some info......but from what I understood from the repairman, the motor module is not giving constant accurate info.  when he switches off the ignition, the computer does not retain the data.....also there is a faint hiss sound coming out of it which he said is not supposed to....so malfunction......on the humidity, a/c heater drain not blocked....sour air is less with no carpets....we re still checking that......by the way, I am from panama city, rep. of panama.....anything you can chip in suggest is well appreciated.....I am tired of spending $$$ on that car and as I said I am stuck with it(almost no resale value)....I just want it to transport me normally.

thx and best regards,
david eskenazi

ANSWER: Hi David,
The 22 code is the most relevant in that it says that the engine coolant temp sensor is off value. If you have the 2.5L engine it is located at the base of the coolant filler pipe's neck. It has two contacts in its plug. It is an inexpensive and easy replacement which should be done unless you find the wires connected to the plug are damaged and thus causing the code. An inaccurate coolant sensor will produce an incorrect air/fuel mixture. Just remove the air cleaner housing to get a better access to it for removal and replacement.
The 44 has to do with the charging system and is designed to charge the battery at a rate related to its temperature. It is not likely related to the engine operations.
The 12 code is common and occurs if the battery is loosely connected or is purposely disconnected in the recent past. So check the shinyness of the clamps and posts and make sure they are firmly attached.
I would not worry about the memory issues. The memory will self-erase if the battery is disconnected, so that is another reason for checking the connections at the battery and also check the connections of the - post clamp wires at their far ends (at the engine/transmission and the nearby body). Loose battery connections or battery wire connections may explain why the computer memory is not holding the codes!
Once you have done all that, then see how things go.
Roland

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

QUESTION: hi roland,

thx for all your help......however, my mechanic / repair shop here are suggesting we change the engine computer module because it is hissing faintly (sound) even after engine is off...thus malfunctioning.....according to them the batt and terminals are connected properly and the charging system is fine....so it all boils down to that computer......it will cost me......part, instalation, and programing incl. labor, discounts, and taxes, around 600 to 700 U.S. dollars.......what do you think I should do?

regards,
truly yours,
david e.
panama, r.p.

Answer
Hi David,
I would be inclined to disconnect the battery while listening to the ecm. You might rather be hearing the nearby battery out-gassing because it is being charged at a slightly too high a current (the code 44 issue), so if the sound stays the same with the battery disconnected that would show it wasn't the ecm. In either case I would go to the sensor which is located behind the front bumper beam on the left side and disconnect its plug. Then measure the resistance between its terminals (which should be 9,000 to 11,000 ohms when the temp. is around 25C). The problem could also just be with its wiring harness so check that too. Maybe fixing the charging issue will eliminate the sound.
If it appears to actually be the ecm I would try to find a used one at a wrecking yard that came from a '95 Cirrus or Stratus that has the same type of engine/transmission as yours, as I believe you would find it would be compatible without re-programming. I would believe you could find one used via wrecking yards. That would be a much more economical solution which you could do yourself. Just unplug the old one and put in the used one.
These would be how I would try to make the car useable without investing more than it is worth.
Roland