Cranks but wont start

Good day. Would you be able to offer me any assistance please. My car just died on me the other day. (Two weeks ago) Limp mode light came on. Cranks but wont start. Diagnostic done (+- six times now) crankshaft sensor error shows. Crank shaft sensor replaced, still same error. Car still wont start. Ecu, wiring and camshaft checked all in 100% working order. Cannot seem to find problem. Could it be the reluctor wheel by camshaft, they want to replace this now, but all of this is costing me money but the problem is still not sorted. Almost in workshop for two weeks now. Assistance will be much appreciated. Thanks.