Abstract: A fault identification system for intake system sensors according to the invention includes a throttle position sensor (TPS), a manifold absolute pressure (MAP) sensor, and a mass airflow (MAF) sensor. A diagnostic controller is coupled to the TPS, the MAP sensor and the MAF sensor. The diagnostic controller implements a throttle model, a first intake model and a second intake model and correctly identifies faults in the TPS, the MAP sensor and the MAF sensor. The throttle model generates a mass airflow estimate. The first intake model generates a first MAP estimate. The second intake model generates a second MAP estimate. The diagnostic controller applies residual calculations on outputs of the throttle model, the first intake model and the second intake model. The diagnostic controller applies a first order lag filter on the residual calculations. The diagnostic controller accesses a truth table to identify faults in the TPS, the MAP sensor and the MAF sensor.