Chrysler Repair: security alarm (factory installed), chrysler new yorker, chrysler dealer

Question
I have a 1991 chrysler new yorker 5th avenue.
The security alarm was set on it and the lock switches were broken inside, so it would not unset when turning the key in the door locks.  I replaced both switches with new ones from chrysler, and tried turning the key in the key switch, and I still get the same result.  The horn and lights do not flash ( they only do that for the first 5 and 18 mins.) to show the alarm is set, but it will not run, just like if the alarm is set.  The car will start and run for about 2 seconds, just like it runs out of fuel,  if you hold they gas feed down it will rev and race for just about the same amount of time, if you pump the gas feed fast and continuosly durring that time it will keep running very rough and backfiring and blowing a lot of black smoke like the air supply is cut off.  I have checked all the switches and connections to make sure that everything is getting a good connection and it is.  I have tried disconnecting the battery and letting it sit for a couple of days, but that didn't work either  I could really us any help, my local chrysler dealer has no idea what it could be or that they even installed a security alarm in the factory.  Thank you for your help so much.
James

Answer
Hi James,
I think you need to do a system self-test that will localize the reason for the "no disarm" that you are experiencing. It is clear that the controller has been told by the theft module to disable the engine from running. So we have to figure out how to get the theft module to send the controller a signal to cancel that out. Try this:
A diagnostic mode is available in the system to verify operation of all monitored switches or circuits. To enter diagnostics, cycle the ignition key to the accessory position 3 times, leaving the key in this position.
Upon entering diagnositics, the park and tail lamps will begin flashing to verify their operation. In addition, the horn will sound twice to indicate that the trunk key cylinder is in its proper position. Returning the ignition to the OFF position will stop the lamps from flashing while keeping the system in diagnostics.
While in diagnostics mode, a horn pulse should occur at each of the following events indicating proper operation:
(1) Beginning with all doors closed, open then close each door. The horn will sound when the door ajar switch closes, and then again when the switch opens. There must be a 1 second delay between closing and opening the switch.
(2) Open, then close the hood. The horn will sound when the hood is opened, and again when it is closed.
(3) Activate the power door locks in both the lock and unlock directions. The horn will sound after each activation.
(4) Rotate the key in each of the door lock cylinders to the unlock position. The horn will sound as the switch closes, and again when it opens. There must be a 1 second delay between changing switch states, or the horn will not sound.
Press the LOCK button, horn will sound
Press the UNLOCK button, horn will sound
Press the Trunk buttoh, horn will sound
(5) Cycle the key to the ignition RUN position. A single horn pulse will indicate proper operation of the ignition input. This will also take the module out of diagnostics mode. For any of these tests, if the switch does not remain open or closed for at least 1 second, the horn will only sound once.
The lack of a horn pulse, during any operation, indicates a switch failure, the lack of that input in the Vehicle Theft Security system module, or a failure internal to the module. Check for continuity at the switch, if this is good, check for an open or shorted wire between the switch and the alarm module. Also, check if the SBEC has been replaced recently. Vehicle Theft Security System will not function until 20 engine cranks.
Thus, note if any of the expected results don't occur and let me know which. There is also a fault tree chart in my '91 manual that may be of help, so keep track of exactly how this self test proceeds. I also have the wiring diagrams and so I can help you check out the wiring.
Don't disconnect the theft module at any time UNLESS the engine is running as that will be another reason for not being able to get the engine controller to go back to the normal functional mode. (Did you happen to do that??) If so, it may require a "reset" using a Chrysler Diagnostic Readout Box.
Roland