The C1111 engine code seems a kind of chassis problem and it is also found from the general meaning of the car. We must not use general meaning for solving the car engine. We will use manufacturer meaning. The dictionary and manufacturer meanings may not similar. You need to get that real meaning for solving the car engine. The engine C1111 OBD2 may also be generated by faults earlier down the line. Such as a dirty MAF sensor might be producing the car to overcorrect in its fuel-trim adjustments. As a result, the oxygen sensors are probable to report fuel mix problems.