> I check it to day, and found that the ecu does not flash on the dash board.
If you turned the key over to enable the igntion, a load of dash lights should come up on the dash, inc the ECU light.
If you see no ECU light then its NOT powered. The reason for a non powered ECU is
1) immobilser still activated or
2) fuel pump relay failure or
3) completly dead/knacked ECU
I would check the fuel pump relay, take it out, give it a few tapes on the on the ground to disturb the spring and arm inside, clean the contacts of both relay and socket, reconnect and try again. A new relay is about £20 from VX delaer.
But as you have installed a new engine and ECU, have you made SURE the ECU power wire is connected to the battery + post? I did the same mistake, the 12v wire is black and I presumed ALL wires that are black are GND connections, so I had the same problem as you, the ECU light never came on hence it was impossible for the car to start. Once I buzzed out the wires with the haynes schematics in the back, I saw my simple problem.