car starts for 2-3 seconds and dies on 1991 Chrysler New Yorker

my 1991 crysler new yorker 3.3L V6 will start up for 2-3 seconds then just dies. Checked the fuel pump, changed fuel filter, found 2 broken bolts in the manafold (took apart totally cleaned and replaced with new bolts), checked for spark only one plug didnt get spark-replaced it. (while checking each plug for spark the car would run (rough) on five plugs. check engine light binks out code 12. please help with any solutions. Thanks

by in South Lake Tahoe, CA on December 22, 2009
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3 answers 1 comment
ANSWER by , January 08, 2010
A code 12 means a bad electrical connection or weak electrical system such as low system voltage.
COMMENT by , April 14, 2016
code 12 is power has been disconnected. It will show till several start stop cycles have been performed. Not a bad code. Information on electrical interruption.
ANSWER by , January 23, 2013
If it has anti theft system activated, it will start briefly then computer will shut it down. Deactivate by unlocking either front doors with key, or if system is malfunctioning, you can ground the ground wire running to the theft module(21 pin natural color connector)under the dash above the glove box. I put in a permanent wire with a momentary switch, so whenever the theft system is activated, I can just push it to reset system.
ANSWER by , April 14, 2016
My Chrysler had a similar problem. First disconnect Battery. Check Voltage. Must be 12 volts or above. If battery is over a year old? It may be loosing power to a short? If Battery is ok. Reconnect & check all circuits. Light when opening door? Fuel pump comes on when key is turned on but don't start. Check as much as you can with out draining battery. Before trying to start after re connecting battery. Go to passenger door & cycle the key 3 times. lock to unlock. Do same on drivers door. Try to start. If no start? check all fuse's & relays in glove box & under-hood. Do NOT trust, "It looks Good?" Get a multi-meter & check. While fuse are out. Check for voltage at fuse location. One side should have voltage & the other side none. Turn on key & do it again. Especially check the fuses that control Alarms, Ignition, Fuel pumps, ABS & Heaters. They can be the source of no start.