Mr ikenna add me too. 08035954944

Pls i have a 406 naija made 2001 model with ew10 engine, the problem is that it brings out black smoke and backfires when driving,consumes alot of fuel, we changed d injector top n nozzles n plugs to no avail, i took it for diagnosis n d say dat its d oxygen sensor wich i changed, d engine check light is always on but wen we diagnose it we clear d faults but it always comes back, stating that the knock n oxygen sensors are faulty. when we clear d faults d vehicle becomes smooth only to go back again after a lil time. now d sayin i should change d sensors again,feel d r doin trial n error only. what i do? Thanks gu