Got A Code 84???

Well I went to Advance Auto Parts here in town to get them to hook it up to their scan tool. The problem I had was with Tranmission kicking/ jolting into gears while driving and slaming from (P or N) to (R or D)...Reverse the worst. When they first did it I got the following codes:
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Diag. Trouble Codes

History Code 60
Cruise Engaged With
Car Not In Drive

History Code P0117
Q D S M #3 Output
Open or Shorted


History Code 84
Ign System Problem
Too Few 24x Sensor
Reference Pulses

Current Code 84
Ign System Problem
Too Few 24x Sensor
Reference Pulses
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Had Advance Auto erase code in Computer. Car drove like new again until I get about five miles down the road and car jolted through gears while downshifting and upshifting. I took it back and the following code was read again.
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Current Code 84
Ign System Problem
Too Few 24x Sensor
Reference Pulses
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I had them look for this code in the Code book they had for this car or other that apply. This Code was not found. They have seem to have Code 83 and 85...but no 84. What up with this? Please Help. Thanks in Advance!!!

Dont know that one.Looked on cadillac forums, it is brake booster sensor,which is tied into the tranny.Caddy also uses 4t80-e trans.Something else you might want to check is your motor mounts.Put your car in gear with your foot on the brake and the hood up and give it a little gas to see if your motor raises to one side.Forward and reverse

Probably no help, but i found a code74 Trans input speed error (4L80-E)

all obd11 codes are p0xxx codes, what is the year of this car? The qdm code may be the driver that controls some trans solenoids, I would have this scanned on a full function trans scanner ( forget AZ, only a trans shop would have this)

Well it is a 1995 Aurora w/ 172,000. I have already check the Motor/Trans Mounts and they look well for a 11 year old car. I have put it into both Drive and Reverse and the engine does not lean to one side or the other. I have notice the car seems to have extrememly more torque than what it has had in the past. It is an ODB I system w/ a OBD II connector. What they were thinking I do not know. I know they were getting ready for the change but they should have left connection the same. A Code 84 does exist I have found out by doing searches for the 24X SENSOR (Crankshft Postion Sensor). But to narrow down the problem I have yet to do. Some people have said they have changed this $200 sensor and fix the car and some have change the PCM and fix the car. Some have said they have did both and not fix the car and they will keep driving the car as is until it goes BOOM. I don''t want to pour to much money in it as I am starting to look for something else. I just want a temp fix where I can get more of a trade value for it and the dealer can fix it the right way. I love this car and maybe I will trade it for a newer model w/ all the updates. We will see.