Chrysler Repair: 92 Lebaron: 3.0L jerky trans., engine diagnosis, diagnostic capability

Question
I have a 92 lebaron that i have had no problems with until just recently when I was driving home from work, my car started acting funny. when i would slowly accelerate from a stop my Trans wouldn't grab, my engine would just rev up for a few seconds and then it would get into gear and jerk the car.  also when i would hold the gas pedal down to keep a steady speed, my Trans would grab once and jerk the car and then quickly do it faster and harder until i took my foot off the gas and then it would stop and wouldn't do it again for a while. and one more thing, when i accelerate and get to the appropriate speed, i will take my foot off the gas, and my car will jerk forward for a split second, as if i had hit the gas and let go. i don't know whats going on but i hope you can help. Thanks

Answer
Hi Andrew,
I am uncertain whether your problem is the trans or the engine itself. Because it hasn't gone into trans limp-in mode (starts and drives only in 2nd gear) it may not be the trans at all. You might get help from using the on-board diagnostics. For the engine diagnosis use the ignition key:
"on-off-on-off-on and leave on" doing this is 5 seconds or less. Then watch the check engine light, which remains "on" to begin to flash, pause, etc. Count the number of flashes before each pause. Then repeat to verify the counts. Then group the counts in pairs to form the two-digit fault codes. Write back with the results, or got www.allpar.com/fix/codes.html for a code translation.
The trans controller also has self diagnostic capability, but it has to be readout using a plug-in reader attached to a receptacle that is behind the fuse door on the lower edge of the left end of the dash. It takes a Chrysler DRB II reader with a data link connector plug (different from the one used to read the engine codes from a receptacle under the hood) so you will probably need to go to a Chrysler dealer to get a readout of its codes. Ask for the numbers, the names, what they mean, and the possible fixes and costs.
I would be inclined to verify the engine is ok first. Then go for the trans diagnosis if the problem continues.
The cost of rebuilding the electronic trans is prohibitive, so don't let this go on indefinitely as it can only do further damage if there is a fault in it. You would be wise to check the level of fluid in the trans via its separate dip-stick. Only use Chrysler brand trans fluid that you buy from a dealer; tell them you have the '92 trans so you get the correct fluid. But don't overfill it either.
Let me know what you learn, please.
Roland