1996 suburban codes;P1100,P1345,P0700

1996 suburban 5.7 and 4L60E transmission both less than 4000 miles. between 60 and 75 mph,there is a noticable miss, and started at about 3800 miles or so.You can watch the tack jump between 1700 and 2200 or so. after scanning with an OBD 2 the following codes keep coming up and we are unable to locate the meaning behind them. anyone have any ideas? the codes are P1100 P1345 P0700 . Any takers? Holding onto vehicle now. at also started engaging the starter when the tranny shifts into 2nd.Other than being haunted or a piece of crap, suggestions are eagerly awaited.
The PO700 is a generic transmission code that needs to be checked out further with a transmission specialized scanner.

The P1345 is the key here. Someone has messed with the distributor, probably thinking they were adjusting the timing but all they were doing is throwing off the synchronization of the injectors to the spark and throwing the rotor out of phase. You will need a professional scan tool to get the offset set to zero and then you can clear the computer and it should run better.