JoeMag

What are each of these items for? Trying to get rid of some old wiring/components that are not being used.

#4 looks like two big capacitors, maybe for old CD ignition?

DonE

What year? I might have the wiring diagram.

sand_man

#2 is the is the ignition cut-off relay:
https://rennlist.com/forums/911-turbo-930-forum/288234-engine-runs-on-as-a-safety-feature.html

A930Rocket

Here you go....

BrianKeithSmith

#4 Looks like 2 "D" batteries wired up straight to a harness.

JoeMag

Yea, I hear ya on the two D batt's. That's exactly what they looked like as I was unwrapping 24 year old electrical tape!

So what is an "air flow sensor/charging pressure relay"? Does that have something to do with the plug you remove to make the fuel pumps work with the car off?

car is an 82

A930Rocket

Mine is square and yellow, but with the ignition on and you press down on the air flow meter plate, it trips a switch and kicks on that relay. It's a safety device. When there is no air flowing, the pumps stop. If you are EFI, I would assume you don't need it.