Hdi not starting occasionally

[Poodle]

I'd be surprised if it was the ecu at fault then. Especially since i now know you changed the fuel filter a week ago, as this is classic fuel pressure problems. Did you use a genuine/high quality aftermarket filter? Could be not flowing enough if it's not a decent one. Could be muck finding its way past the filter if you haven't got that spring washer. Did you drain the filter housing when you changed the filter? If not that could have also let some crap through into the high pressure system.