Circuit/System Testing
IMPORTANT:
You must perform the Circuit/System Verification before proceeding with the Circuit/System Testing.
- Start the engine. The Manifold Absolute Pressure (MAP) and SC Inlet Pressure Sensor parameters should decrease and closely match each other.
- Engine running, inspect for any of the following conditions:
- Vacuum hoses for splits, leaks, and proper connections
- Air leaks at throttle body mounting area and intake manifold sealing surfaces
- A supercharger bypass valve that is binding or incorrectly adjusted
- If any of the above conditions are found, repair as necessary.
- While taking a snapshot of the engine data list, perform the following actions. Idle the engine. Increase the engine speed slowly to 3,000 RPM, then return to an idle. Observe the Mass Air flow (MAF) Sensor parameter frame by frame with a scan tool. The MAF sensor parameter should change smoothly as the engine speed is increased and is returned to idle.
- If the MAF sensor parameter does not change smoothly as the engine speed is increased and is returned to idle, refer to DTC P0101 .
- Engine running, slowly depress the accelerator pedal to a WOT position, then slowly release the pedal while comparing the TP Sensor 1 and TP Sensor 2 parameters. The difference between the parameters should be less than 4 percent.
- If the voltage is 4.8-5.2 volts, then proceed to the next numbered step.
- If TP Sensor 1 and TP Sensor 2 parameters differ more than 4 percent, refer to DTC P0120, P0122, P0123, P0220, P0222, P0223, or P2135 .
- Ignition OFF, inspect the throttle body for the following conditions:
- Loose or damaged throttle blade
- Broken throttle shaft
- Any throttle body damage
- If any of these conditions exist, replace the throttle body assembly.
CAUTION:
Turn OFF the ignition before inserting fingers into the throttle bore. Unexpected movement of the throttle blade could cause personal injury.