TD5 injector disbalance / engine runs rough / white smoke

I have an issue with my Discovery 2 TD5 where I had a while ago an increased oil level due to probably fuel getting in the engine. We planned to change the injector seals but then had white smoke and stopped immediately. We changed the injector seals, also the copper ones but the engines runs very rough now and have no or less power. Checking with a Nanocom we see a disbalance. Injector 1 is around 21 in idle mode and the other ones try to compensate. Cleaned then the harness plugs and the connector of the ECU as there was some oil but not really excess. I felt small improvement after that but I can be wrong. The engine still runs rough. After looking in my history I saw the balance looking good in the past, but already had 6 months ago an increased disbalance on 1 which I didn‘t took care off as she was running smootly and had no engine problem. There is not really blue smoke or white and some black smoke by accelarating. What could be the cause? Anybody ideas? I have been reading so many things…

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