Injectors not firing while cranking - MK5 Engine Swap

[Rynny]

Hey all,

On my MK5 Jetta 2.0 TFSI (was originally a TDI but I engine swapped it), my injectors are not receiving battery positive or being grounded to fire by the ECU while cranking (so no start), when I start the car with starting fluid they start firing the minute the car turns over, what would be causing this?

Main Relays and fuel pump relay are all good, I've got fuel and rail pressure, spark, good airflow and MAF reading, etc., the ECU just WILL NOT fire the injectors unless it's manually fired by other means (starter fluid)

On a separate note I have replaced: fuel pump relay, main relay, fuel pump control module, crankshaft sensor, camshaft sensor, coolant temp sensors

[MIG]

Check your wiring diagrams and see if the injectors are high-side or low-side switched; that will tell you if you should see voltage at the injectors.

Then do an output test on the injectors via VCDS or similar that should rule out any other issues.