stalling, 1998 1.9 t4

[gregamar]

when starting the car it will run fine for a few seconds then stall, it is worse when cold but still does it hot, also does it when stopping for lights ect,
but not all the time, some times i get light up but not always, ive plugged it to my obd11 reader many times and get different fault, clear the code or replace the part it says but still the same, ive changed, fuel pump and filter, spark plugs, air mass, ignition coils, there is no air leaks, and all the temp sensors are reading correctley,throttle body is clean, im thinking of replacing the ecu,
any idaes before i do that would be great, thanks. greg