Ford 3.0 2002 года не заводится с третьей попытки

Я перепробовал всё, но безуспешно. Это продолжается уже около года, и это не проблема. Яve let it go until more info on the subject was available. Well now have had to replace the engine with a used one that I got to drive and had no problems. All components from the used motor were used including the Mass air flow. I thought it was cured after that but the starting problem came back like a ghost after 3 days. [I reused the original PCU ] Does any one have any insight on what I should be looking for ,some say the mechanical key switch but I think not. Note after a time it would sometimes start on first try after driving a few blocks to gas station but not always. EDIT to post 3 days ago after a year of starting on 3rd try only I decided to extend the cranking time witch I tried before and didnt work also I dont like to do because both motors start right now usually. but for the last 3 days its been starting on 2nd try with a 2 sec. bump . Kind of an annoying problem witch I буду искать ответ ещё долго после того, как этого автомобиля не станет.