Chrysler Repair: Engine Hesitation, engine hesitation, dodge dynasty

Question
I have a 1991 Dodge Dynasty 3.3  It idles pretty good but when you put it under any load it misses really bad and wants to die. This same thing happened about two years ago and I replaced the coil pack and it ran great. I performed the same test this time but it seemes o.k.  (The test is pulling off the plug wires one at a time and checking for a change in idle. Last time when I pulled one of the wires and i didn't have any spark so I knew what it was. This time I have spark on all wires.  

Answer
Hi Brandon,
Have you pulled a spark plug to see if it looks o.k.? and how many miles on your plugs? There might also be a problem with the fuel filter being plugged up, or a fuel control issue that might have been detected and logged as a fault code in the engine controller memory.
The most useful thing to do would be to try to get the fault codes that may stored in the engine controller memory to readout. Try using the ignition key: turn it "on-off-on-off-on" and leave it "on" (doing this quickly, no longer than 5 seconds). By "on" I mean just the normal position when the engine is running, not the cranking position. The 'check engine'light will remain on when you leave the key in the "on" position with the engine still not running. But then watch the 'check engine' light to begin flashing, then pause, flashing, pause, etc. Count the number of flashes before each pause and keep track of the numbers. Repeat the readout and verify the counts are correct. Then group them in pairs in the order that they came out, thus forming two digit numbers. You may notice that the pause is shorter between the digits of a given number, and longer between the numbers themselves. Then send me a 'follow-up' question telling me the results of your readout. By the way, 55 will be the last number (two groups of 5 flashes each) and that is the code for "end of readout".
There is also an essay on fault codes at the site:
http://www.allpar.com/fix/codes.html
which gives the meaning of the code numbers. But then you need to get specific info for what exactly might be the diagnostic tests or parts to replace to complete the repair.
But do check the spark plug and maybe consider a fuel filter if your hasn't been changed in a large number of miles.
The final possibilities are an egr valve that is sticking open and an intake manifold vacuum leak. That is a pretty long list of possibilities, but try to get the codes and whatever else seems easy and write back with the results.
Roland