So we put in new AMS 2.2L engine + turbo kit but having trouble to startup the car, as soon as we started cranking the CEL pops out and reads P0340 (intake camshaft position sensor), the motor doesn't turn over.

We have checked the following and confirmed they are in good order:
- all the cam timing marks are correct
- scoped both the intake & exhaust camshaft sensor are in good working order (bought a new one as well)
- we unplugged the ECM and confirmed the cam sensor wiring gives constant 5v
- the camshafts are brand new GSC S2

Now when we plugged the ECM back, the car wouldn't even crank up (it was cranking before).

If anyone has any idea to this problem please let me know.