Re: 01 jgc v8
Welcome to the garage.
The large box where the vacuum line goes to is the vacuum reservoir. It keeps a constant vacuum for the cruise control to work well.
Strange that the battery started to give problems after you removed it. Was all ok before the battery removal?
Did you check if the new battery is charging normally? Engine off and battery fully charged should give about 12.8V. Engine running should give 13.5-14.5V.
If the PCM looses the IAC settings, then it should relearn them by itself. If you had broken vacuum lines for some time, then the PCM probably closed the IAC completely, to try to control the idle speed. Now that the vacuum leak is solved, it has to reposition the IAC to control the idle speed. You probably have to keep your foot on the accelerator for a longer time, for the PCM to be able to relearn.
Cleaning the IAC is not a bad idea if it was not done for a long time.
TPS is a sealed unit and can not be cleaned. If it gets faulty, you will need to replace it. You could check the TPS by using a scanner with live data. Idle TPS % is around the 12%, but at least should be a steady indication. If its jumping a bit, then the TPS is at the end of its usefull live.