First start after 25 years - problems Options

[spencercanon]

Hi all this is my first post here! I recently picked up a ’75 1.8 that was last registered in 2001! Pretty good barn find, in my opinion. It was up in the high desert of California, so no rust, great mechanicals, all the electrics work. Just flaking paint, decayed interior …and an engine that probably hasn’t run since the Clinton Administration.

The TLDR is the car has started and run for 10 seconds but now won’t start at all.

A quick timeline of what I’ve done/tested:
- Dropped the engine, adjusted valves (encountered something strange that I’ll ask about later)
- Old starter could barely turn the engine over. Replaced it with a hi-torque.
- good compression
- Replaced the old broken bellows thermostat
- New fuel lines, vac lines, spark plugs and wires
- deleted EGR system
- Fuel pump was getting power but dead - replaced it.
- Coil’s good. Cap and rotor look good. Points gapped.
- The L-Jet AFM had been opened and the adjustment wheel inside was so loose that it the flap wasn’t closing fully so the pump was running continuously. I rotated the wheel until there was enough tension to turn off the fuel pump. (I would have normally never touched the AFM!)

Put the engine back in and the car started on the key immediately, ran for 10 seconds and died. I tried again, it started and ran for 5 seconds, then popped loudly back up the intake with enough force to blow the intake boot off the AFM. Since then, it hasn’t started.

Couple notes:
- after the pop, I felt like the intake pipe connector hoses were probably leaking, so I put hose clamps on them. With those clamped down and fresh vac lines everywhere, I’m pretty sure there aren’t any more leaks.
- oil filler breather nipple broke so I’ve taped it off until I can get a new one. But I’m not sure how this affects the vacuum… should it be left open for now?
- I don’t know the fuel pressure but it does have a new pump and lines so I’d be surprised if pressure is the problem.
- tested injector ballasts and got correct ohm readings
- It did start and run on its own spark and fuel, so I assume ECU and injectors are OK.
- the AFM is obviously an issue … probably considerably off. But again, the car did at least start a few times.

So now what?
- I’d like to check/test anything I can before I start buying replacement components.
- Are there baseline settings for idle speed screw, and at least a “best guess” AFM setup?
- Should I just buy another AFM now, knowing this one may never be right again?
- could the intake backfire have damaged something?

Thanks in advance for your thoughts!