Chrysler Repair/Poor idle, stalling but no codes: '95 LHS
I am having a similar problem with my 1995 Chrysler LHS as the gentleman with the misfire, but I have no codes at all. I did have a dead cylinder so I fixed the problem by replacing the coil - fine now. Now I stop at a red light and the car shakes, drops in idle, and 75% of the time just stalls. BUT it doesn't just do this in gear, sometime I will get the flux in the idle and stall when it sitting in park - just not in front of any mechanic! It seems to happen more when it it warmed up/hot (although not overheating or anything) or the air conditioning is engaged although there is no real set pattern of when it happens. I have had it with this car, I am stranded 1600 miles away from my house because of it, any help/ideas will be greatly appreciated. Thanks.
Let's assume that the ignition system is o.k. and think about mixture. One possibility is that the temp sensor is not accurate but not so bad as to cause a code, and similarly with the manifold absolute pressure sensor, but you would need a voltmeter to access whether whether either of those could be true. So let us sit on those until we 'exhaust' the other possibility and you let me know if you have access to a volt-ohm meter.
I have another idea, one of my favorites when bad idle rears its ugly head. I would take a look at the exhaust gas recirculation valve which is located behind the engine near the air intake throttle valve. It is mounted in a pipe that runs between passenger side exhaust manifold and the air intake manifold. The valve is mounted horizontally and has a valve stem between its round vacuum actuator top and the body of the valve attached to the pipe, inside the flange that connects the two parts. The stem has a slot into which you can insert the tip of a flat-bladed screwdriver so as to lever the stem back and forth against spring action which should move freely and close tightly. If the stem seems to be sticky so that stem doesn't close all the way by spring action, then you can try spraying some penetrating solvent like WD-40 on the valve stem to freeup its motion.
If the valve is sticking slightly ajar it will make for a rough idle and poor acceleration such as you describe because the mixture is too dilute. It is one of the most common causes of this symptom. So see if you can find the valve and check/lubricate the stem. To check it in motion you can rev the engine from idle to 2500 rpm and back to idle and watch to see if the valve stem moves freely in both directions to the extreme open and closed positions. It may be that the interior of the valve is cruddy so that might require that it be unbolted from the pipe where it it attached and cleaned. But chances are good it will only be a sticky stem. Feel free to write back with the results and other questions you might have.
Good luck on the troubleshooting and maybe you can get home soon,