Help with problem....

[1000_eyez]

I have a 1989 535i 5 speed. Trying start and it just turns over and over without starting. I tried many times...drained the battery. Jump starting does the same...just turns and turns. I recently bought a used ECU and put that in. Same ECU number as the one I had. Could that be the problem? The reason why I had put another ECU in is because the other one I had ruined...my stupid fault...but brfore that it was working great. Now with this other one it doesn't want to start...just turns and turns until battery is dead. Any ideas would be great.

[1000_eyez]

Also before with the original ECU, there were no fault codes and running as normal. The only problem I had was the heater core fogging my window and the smell through the vents.
So, my guess, that it is the ECU. I will have to look at buying a differant one.
I guess I'm talking to myself
:D