Hi all, let me apologize for the long post in advance.
I have a 89 G syncro with 1P motor.
The car originally had the ECU marked as 037906022AR from factory, and it was running just fine.
For now let me call this AR as AR-1, because there will be another later.
By hearing all the goodies from ChrisS, I have decided to swap the ECU with the one he sent me, the last 2 suffix BB, which is supposed to be the EU GTI ECU.
After fitting, somehow the car smelled gas, and even after 30sec of cranking, the motor did not start.
I guessed it is shot someohow, and I then put the AR box back in, and it then ran fine.
But I could not give up fancy of having few extra hp so I obtained BC ECU off ebay and fit it. It felt like the car ran stronger than when it had AR-1.
Last November when my car needed to have it checked bi-annually, I put the AR box back in again, and the same thing as the BC, it kept cranking but did not want to start, with lots of gas fume.
Eventually it did start, but lots of black smoke and strong CO smell out of the exhaust.
I figured the AR-1 is shot, so started looking for another and did last week, AR-2 that I have now, meanwhile the BC ECU was put back in the mean time and it ran fine.
Yesterday I put the AR-2 in, and once again the same thing, it will not start!! It seems as if there is no spark! I have swapped nothing but the ECU only, but it does this over 3 ECUs!!
Can anyone tell me what is wrong with my G please??
Ultimately I want to use the BB ECU that ChrisS has sent.
Many thanks in advance though.
I think the fault is that the earth connection on the corner of the cam cover (flywheel end) is not making a proper connection,
this will cause all sorts of problems and can at worst can even fry your ECU,
so please check/clean ALL earth connections/cables as I am 99.9% certain that this is the problem. 
Hi Shinya, Any news on this yet?
Possibly you have a broken wire or an intermittent connection on your ECU plug, you could try spraying this with a switch cleaner/WD 40 type spray