Coordinated torque control security systems and methods

1. A control system for an engine, comprising:

a selecting module that:

selects one of (a) target intake and exhaust cam phaser angles and (b) measured intake and exhaust cam phaser angles; and

sets selected intake and exhaust cam phaser angles based on the selected one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles, respectively;

a target air per cylinder (APC) module that determines a target APC based on a target spark timing and the selected intake and exhaust cam phaser angles; and

a phaser scheduling module that determines the target intake and exhaust cam phaser angles based on the target APC and that controls intake and exhaust cam phasers of the engine based on the target intake and exhaust cam phaser angles, respectively.

2. The control system of claim 1 further comprising:

a first torque estimation module that determines a first estimated torque output of the engine based on a manifold absolute pressure (MAP) measured using a MAP sensor; and

a second torque estimation module that:

determines a second estimated torque output of the engine based on a present APC of the engine and the measured intake and exhaust cam phaser angles; and

determines a third estimated torque output of the engine based on the present APC of the engine and the target intake and exhaust cam phaser angles,

wherein the selecting module selects the one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles based on the second and third estimated torques.

3. The control system of claim 2 wherein the selecting module selects the one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles based on a difference between the second and third estimated torques.

4. The control system of claim 2 wherein the selecting module selects the one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles based on a sum of values of a difference between the second and third estimated torques determined over a predetermined period.

5. The control system of claim 4 wherein the selecting module selects the target intake and exhaust cam phaser angles when the sum is less than a predetermined value and selects the measured intake and exhaust cam phaser angles when the sum is greater than the predetermined period.

6. The control system of claim 2 wherein the selecting module adjusts the selected intake and exhaust cam phaser angles toward the selected one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles, respectively, by up to a predetermined amount each predetermined period in response to a transition in the selected one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles.

7. The control system of claim 2 further comprising:

a target manifold absolute pressure (MAP) module that determines a target MAP based on the target spark timing, the selected intake cam phaser angle, and the selected exhaust cam phaser angle; and

a boost scheduling module that determines a target duty cycle of a wastegate of a turbocharger based on the target MAP and that controls the wastegate of the turbocharger based on the target duty cycle.

8. The control system of claim 7 further comprising:

a target area module that determines a target opening of a throttle valve of the engine based on the target spark timing, the selected intake cam phaser angle, and the selected exhaust cam phaser angle and that controls the throttle valve based on the target opening.

9. The control system of claim 8 further comprising a target mass air flowrate (MAF) module that determines a target MAF into the engine based on the target APC,

wherein the target area module determines the target opening based on the target MAF and the target MAP.

10. The control system of claim 7 wherein the target MAP module determines the target MAP further based on the first estimated torque and the second estimated torque.

11. A control method for an engine, comprising:

selecting one of (a) target intake and exhaust cam phaser angles and (b) measured intake and exhaust cam phaser angles;

setting selected intake and exhaust cam phaser angles based on the selected one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles, respectively;

determining a target air per cylinder (APC) based on a target spark timing and the selected intake and exhaust cam phaser angles;

determining the target intake and exhaust cam phaser angles based on the target APC; and

controlling intake and exhaust cam phasers of the engine based on the target intake and exhaust cam phaser angles, respectively.

12. The control method of claim 11 further comprising:

a determining a first estimated torque output of the engine based on a manifold absolute pressure (MAP) measured using a MAP sensor;

determining a second estimated torque output of the engine based on a present APC of the engine and the measured intake and exhaust cam phaser angles;

determining a third estimated torque output of the engine based on the present APC of the engine and the target intake and exhaust cam phaser angles; and

selecting the one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles based on the second and third estimated torques.

13. The control method of claim 12 further comprising selecting the one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles based on a difference between the second and third estimated torques.

14. The control method of claim 12 further comprising selecting the one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles based on a sum of values of a difference between the second and third estimated torques determined over a predetermined period.

15. The control method of claim 14 further comprising:

selecting the target intake and exhaust cam phaser angles when the sum is less than a predetermined value; and

selecting the measured intake and exhaust cam phaser angles when the sum is greater than the predetermined period.

16. The control method of claim 12 further comprising adjusting the selected intake and exhaust cam phaser angles toward the selected one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles, respectively, by up to a predetermined amount each predetermined period in response to a transition in the selected one of the target intake and exhaust cam phaser angles and the measured intake and exhaust cam phaser angles.

17. The control method of claim 12 further comprising:

determining a target manifold absolute pressure (MAP) based on the target spark timing, the selected intake cam phaser angle, and the selected exhaust cam phaser angle;

determining a target duty cycle of a wastegate of a turbocharger based on the target MAP; and

controlling the wastegate of the turbocharger based on the target duty cycle.

18. The control method of claim 17 further comprising:

determining a target opening of a throttle valve of the engine based on the target spark timing, the selected intake cam phaser angle, and the selected exhaust cam phaser angle; and

controlling the throttle valve based on the target opening.

19. The control method of claim 18 further comprising:

determining a target mass air flowrate (MAF) into the engine based on the target APC; and

determining the target opening based on the target MAF and the target MAP.

20. The control method of claim 17 further comprising determining the target MAP further based on the first estimated torque and the second estimated torque.