98 Jeep Grand Cherokee Stall on Start up and Shifting issues

As stated above I have a 1998 Jeep Grand Cherokee, I just had the engine and transmission replaced and am having the same problems I had before the engine failure. About 30 seconds after start up the engine sounds like it is trying to stall out and you can smell the fuel. I have replaced the AIC and TPS. I tried resetting the Computer by disconnecting the Positive terminal and let sit overnight… That did not work. It is also shifting poorly, for about 10 minutes of driving then seeming to correct itself. I am guessing all of these are part of the same problem. My next step is to change out the MAP sensor. If that doesn’t work I am unsure what else to do beside take it in to the dealership. I am tiring of spending money with no fix in sight and the way it is shifting I am afraid it is damaging the engine due to the high RPM output during the shifting process. Any help would be greatly appreciated.

Has The “Check Engine Light” Been illuminated ? Have You Got Any Trouble Codes For Us ? Any Help Would Be greatly Appreciated.

CSA

No check engine light. I have read in a few forums that it is more than likely a bad PCM. Apparently the PCM on this model is notorious for shorting out and losing information. I have reset it and done the two screw fix…backing the two middle screws on the pcm is supposed to correct an error that causes it to short out. Just did this and the idle seems to be corrected. It still shifted poorly with high rpm output during the shifting process. I also noticed that my oil pressure is fluctuating between 30-45 it was normally steady at 45 before now it is jumping. Replacing the PCM may be my next step.