Hello , i have zafira b 2007 year with CNG factory with engine z16yng . i have removed the CNG tank , because on my country doesnt have CNG... for 6 months it was running perfectly . now it show error only for CNG(3dtc) and start for 30sec and after switch off , and ecu didnt respond for 5minutes,,,, i have seen that opel 2005+ with CNG doesnt have CNG ECU , all information is at engine ecu for petrol+cng(all wiring are attached petrol+cng and go to ecu petrol MT35E 2.4) ,,,, i have changed ecu with astra h z16xep (MT35E 2.3 ), i have coded the immo and now car start for 3sec and switch off , but have 15dtc around petrol and can bus HIGH as doesnt have communciation with ecm... can anyone help me because i have 1months of making test of all the system ?! thanks everyone , any help will be appreciated ...