after a long time,,,,hpdi weirdest problem

[BastiaanMBok]

some time ago I posted on this site regarding the hpdi filters issue etc. changed them all and the engine (300 hpdi)has been running like a dream,,,till yesterday.
this I truly dont know,havent put the diagnostics on it yet.
but maybe someone has the answer.
this is what happens,it starts great,it takes of up to 4000 rpms,then as if some one is switching of a cylinder at the time .very gradual,very precise in timing.
it will go from 6 to 5 cylinders, after 3 seconds it will go from 5 tp 4 cylinders,then after 3 seconds it will go from 4 to 3 cylinders,,,then it does it in reverse: after 3 seconds it goes from 3 to 4 cylinders,after 3 seconds from 4 to 5 cylinders,and after 3 seconds from 5 to 6 cylinders....this proccess just repeats itself if you keep the throttle open...this has me baffled.....
some one got an idea????bad injector driver,ecu,some kind of sensor?? etc?
hate to take my laptop on the boat,,as it is moored at my pier and winds are high .lots of salt that my laptop doesnt like.
hope to get a reaction somewhere
regards to all
Bastiaan M Bok

[BastiaanMBok]

got no replies,but I think I got it worked out.
my ecu does not send any alarm signals.I have tested this by disconnecting the temp sensors..it does not show up on the alarm or the diagnostics.
I changed the ecu with another one,,and now I have a constant alarm,and seems to be an oil level switch in the engine tank.I replaced the oil level switch assembly,and all alarms are gone. it makes sense,as it throws the engine in limp home...allthough a strange limp home. it just circulates in between 2500 and 2000 rpms.
the original ecu has issues,,but when put back with the oil switch assembly replaced,runs perfect again,,,but NO alarms.
one question,,,what is the difference in the 300 hpdi ecu and the 250 hpdi ecu??I see online there is a difference in the partnumber. the engines 250 hpdi and 300 hpdi are indentical. differences i could see are the different partnumber ecu ,,and watercooling on the intake manifold.
cheers
BMB