more problems showing up

So i finished all my little fixes on the 92 sport. Now im having a few problems.

1. The Battery shows 12v when driving and only 10v when i kick the a/c on???

2. Oil pressure is at 20 when stopped then when i start going it raises to 40 then when i get to a steady speed over 40mph it goes back to about 30ish???

3. When i shut the jeep off there sounds like its ticking from the bottom part of the engine more on the drivers side???

Your not charging or not charging enough. Check with a voltmeter at the battery terminals--should read about 12.5 volts static, and 13~14.5 volts with the engine running.

Put a mechanical oil pressure gauge on it to determine actual pressures. If you have any high pressure leaks--at the OFA or sending unit--that will cause lower pressure readings. There are reported issues of low oil pressure readings with cheap oil filters--what brand are you currently running?

You will need to be more specific on the sound. Get a 3' piece of vinyl tubing, 1/2" or less I.D., stick one end in your ear and then move the other end around the engine compartment to "isolate" the sound. Internal combustion engines will "tick" when cooling down.

not sure what filter it has....just bought it a two months ago and it needs an oil change (bought a wix filter for it )

im also pretty sure the ticking is the new muffler i put on