Battery drain, alternator problem?
 

I noticed slow starts which got worse until the battery died. Jumped it right up. Hooked up a battery tender. I have not done a parasitic draw test yet but got a voltage meter. I see that with everything on it is under 13v. Could this be a sign of the alternator going. I will check all the ground wiring since I see comments about it.
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Idle, no accessories
https://cimg9.ibsrv.net/gimg/rennlis...670835a0ca.jpg

https://cimg7.ibsrv.net/gimg/rennlis...1753c15586.jpg
Side markers only
https://cimg3.ibsrv.net/gimg/rennlis...8ccf82288b.jpg
Headlights on
https://cimg0.ibsrv.net/gimg/rennlis...4b3cfe3054.jpg
Headlights and fog light
https://cimg6.ibsrv.net/gimg/rennlis...a69ef28afc.jpg
Headlights, fog lights, radio on
https://cimg3.ibsrv.net/gimg/rennlis...e0a3558be4.jpg
Headlights, fog lights, radio and AC fan on high
https://cimg5.ibsrv.net/gimg/rennlis...101e975a39.jpg
Headlights, fog lights, radio, AC fan high and AC compressor running.

Check your battery cables for any corrosion.

Caveman opinion is those voltages look ok with those bus loads and at idle. Based on these idle voltages not an alternators issue.

How old is your battery?

Check the readings when the car is fully warm vs at cold start. Its possible that voltage regulator works when cold but not when its hot. That would mean the vr is failing. Clean the contacts as well. The fan sucks in tons of dust and the connections don't stay clean after a while.

Hi J,
Before looking too deeply for an expensive solution check your alternator belt, that it is not too loose. In my experience, a failed alternator never archives the required voltage regardless of load.
Andy

New battery around September last year. Going to do some troubleshooting. Thanks for all the pointers.

Check the ground connection from starter to chassis

I added a TopDon BT100 battery tester to my tool box a while ago. Handy addition and about $50 on Amazon. Used it on the 997 and found the battery was on its last legs after 8 years. May be worth purchasing.