Chrysler Repair: 88 New Yorker dies when hot, sensor unit, latter possibility

Question
I have a 88 New Yorker with 3.0L V6, 155K+ miles.
When the engine gets hot the engine will start running rough and die.  I have replaced dist cap and rotor after fault codes of 11&54. That got rid of the codes. Still same problem. I changed coil with no luck and now find out that there is no voltage to the coil (+12v) when hot and engine dies.  Once the engine cools down, no problem. Any ideas.
Jerry

Answer
Hi Jerry,
While the 11 and 54 codes may be gotten 'rid' of, I seriously wonder if they might not have returned because those should more likely have been cured by changing the photooptic sensor inside the distributor rather than the cap and rotor which are unrelated to those codes. The 11 and 54 both refer to signals from that double sensor unit not being seen at the engine controller which then prompts the controller to turn off the ASD so as to prevent both spark and fuel pumping. You have observed that effect with the loss of the 12V at the coil (but you might double check that what actually happens is that you get 12V for about 1-2 seconds when you start to crank the engine but then it drops away. That is a dead give away for loss of the distributor signals phenomenon). If you don't get 12V At All then the ASD relay may be bad when it gets hot. But I suspect that your sensor unit is the cause of the problem, or possibly it could be a problem between it and the controller involving the 2 plugs or their wires. I can give you the pin numbers at the controller if you want to check out the latter possibility. I don't know why the 11 and 54 went away (they will erase if you disconnect the battery for a few minutes) but check again to see if they haven't returned which would prove the need to replace the photooptic unit. These also tend to fail when they get hot, then self-repair when they cool. So it all "hangs together".
Roland