So I'm the lucky buyer on that '72 145 near the NY/Canada border. It's a '72, D-jet, and I was pleasantly surprised to find out that it's in fact a MANUAL. Woohoo!
I've worked a lot on k-jet and have my '79 running like a top, but this is my first time with a D-jet car. It ran last year per the owner and has been parked since. I'll just need to get it running enough to park on a trailer.
Planning on bringing a known good 240 battery and a jump pack, anything special I should know about D-jet to help get the car mobile?
It's an open loop system, no feedback to the computer. There's a little secret knob on the side of the computer that affects overall fuel trim. I had to discover this myself, couldn't for the life of me figure out what it did. If it idles really rough, you can try adjusting this knob to see if it helps out. It can compensate for clogged or poorly flowing injectors, until you get them cleaned. If it's still running really rough, systematically remove individual spark plug wires to ensure the engine is firing on all cylinders, repeat with injector wires. Ohm test all injectors to make sure they don't have any shorts or discontinuities. I think they're supposed to be around 13-14 ohms iirc. Inspect very carefully the condition of the injector hoses. They're really prone to cracking after 40+ years, you really don't want a fuel leak right above the exhaust manifold. Gap your points if it still has points. Remove carbon build up with sandpaper if it's bad. ohm test spark plug wires to make sure they're even and in spec, I think 1.8 Kilo-ohms is somewhat normal...
A huge and extremely common occurrence is the auxiliary air valve and cold start injector having issues, whether that's CSI stuck open or leaking, AAV stuck open or cold, etc.
Using hose clamps to stop fuel flow to CSI and also stopping airflow in/out of AAV can help rule out those commonly faulty components. The car will be difficult to start when the AAV & CSI are disabled, you'll need to feather the throttle to keep it alive for the first ~30 seconds or so before it will be able to stay idling on its own.
Adjust the fuel pressure regulator with a rent-a-tool autozone fuel pressure testing kit, make sure its at 30psi (greenbook calls for 29.8 if you're extra fancy), assuming your fuel pump works. Turning the key to pos2 (maybe pos1?) should engage the fuel pump to prime and pressurize the system, this should be audible as a buzz for about half a second or so.
You can take off the valve cover and crank the engine with fuel delivery system disabled and observe the valves opening, ensure all of them are moving and opening to the same extent as the others.
Also, congratulations!!! I posted that car. How much did you snag it for?