Engine starts but will not run for more than a few seconds

[Batmanbat4]

Hello,

I have a 1981 FI spider that has recently given me many issues. I have already checked for spark, compression, fuel, swapped the fuel injectors and injector relay, and ECU with one from a working car, and confirmed proper timing. From what I can tell the engine is only running on the cold start fuel injector as when it is unplugged the engine will not run at all. The engine will sometimes backfire through the large rubber air intake passage. When I turn the key the engine will crank and start very roughly but will die out after a few seconds or when any gas is applied. I was wondering if any of you have had a similar problem or know how to figure this out.

Thanks

[TX82FIAT]

check MAF, fuel filter and fuel pump. A few seconds of running tells me you have fuel and then the system shuts itself off, Why? A bad MAF or a clog in the fuel line that lets a little fuel pass until it reclogs is a thought.

[alternative]

Same problem but I've noticed with my FI '80 is that sometimes it starts and runs perfectly until I shut it off, then no start again. I'm starting to think maybe the timing is misaligned and somehow slips back into time every 5 or so attempts to start. If my theory sounds crazy it's because I've exhausted every other option on this car.