Hi, forum. I have a similar problem: 1993 Chrysler LeBaron AA body, 3.0L V6, new manual 5-speed transmission installed 2.5 years ago. Driving along at 55 mph when suddenly the engine quit. There was no juddering, no hesitation, just instant stoppage when it quit, as though the key had been turned off.

The problem has been traced to no spark. Coil input indicates max of 5v. during cycling. All wire and hose connections I've examined look good. Key: I get no diagnostic codes from the ignition-switch method. The engine light does not come on; only the Check Gages light. All gauges work fine. Cranking 5-10 sec. gives an indication of oil pressure, so the oil sender is okay.

Disconnected battery for 1/2 hour. Wiggled all wires I could reach. Reconnected battery and while cranking to reestablish possibly lost diagnostic codes the engine started, ran like a top, and 20-30 sec. later quit again. Still gave no diagnostic codes and no 'Check Engine' light.

I heard a slight moaning sound coming from the right side of the engine compartment while cranking the engine right after it quit after 20 seconds in the above example. The engine light came on briefly and then went off. It has remained off ever since.

I have all the books and am following the specific instructions in the "Electrical, Fuel & Emissions" book, section 14. Everything I can reach all seems good. There are a few wires I can't get at (snow; wet ground; carport, not garage). Accordingly I have questions:

1. Would a diagnostic tool get codes I can't get with the ignition key?
2. I have not, for the past 3-4 years, ever had any sort of alcohol in the gas. Our premium here is alcohol-free. Could this engine stoppage be the result of icing/water? [Temperatures have been below freezing at night and up to just over 30 in the day. The car had been running about 10 minutes down the highway when it suddenly quit.]
3. I put a can of Heet into the tank last night, which currently is 3/4 full. I.e., 10-12 gallons or so. I cranked the engine for 5-10 seconds to try to circulate the Heet and then let it sit overnight. Today still no luck.
4. What's the 'LM' mentioned in this thread?
5. Any ideas?
Thanks to you all for your kind help in the past.
..........RayO