hi, it`s been two weeks since the problem started, seems the engine is missfiring, it started occasionally when i boosted, then when the engine was cold and after 10 miles of use it disapeared but now it is since the moment i start it and it wont go away, i changed spark plugs, checked for spark, i am not getting codes, changed fuel filter, checked the grounds, checked timing and it is 10 degrees with diagnostic box jumpered, i am running a map ecu, the tuning was perfect and i know there is no way it will loose the data, when i changed the spark plugs i noticed just number 3 and 4 are richer, they look very black compared to the rest. What can be the cause?