I would test both the tps and map sensors.
map sensor is here:
Testing
Check the Manifold Absolute Pressure (MAP) sensor circuit as follows:
Ignition OFF, disconnect the MAP harness connector at the MAP sensor.Ignition OFF, test for less than 5 ohms of resistance between the low reference circuit terminal 2 and ground.If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 1 and ground.If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.Verify the scan tool MAP Sensor parameter is less than 1 kPa.If greater than the specified range, test the signal circuit terminal 3 for a short to voltage. If the circuit tests normal, replace the ECM.Install a 3A fused jumper wire between the signal circuit terminal 3 and the 5-volt reference circuit terminal 1. Verify the scan tool MAP Sensor parameter is greater than 126 kPa.If less than the specified range, test the signal circuit terminal 3 for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.If all circuits test normal, test or replace the MAP sensor.
Check the Throttle Position (TP) sensor circuits as follows:
Ignition OFF, disconnect the harness connector at the throttle body.Ignition OFF for 90 seconds, test for less than 5 ohms of resistance between the low reference circuit terminal C and ground.If greater than 5 ohms, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM. Ignition ON, test for 4.8-5.2 volts between 5-volt reference circuit terminal E and ground.If less than 4.8 volts, test 5-volt reference circuit for a short to ground or an open / high resistance. If the circuit tests normal, replace the ECM.If greater than 5.2 volts, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM. Verify the scan tool TP sensor 1 voltage is less than 0.1 volt.If greater than 0.1 volt, test the signal circuit terminal D for a short to voltage. If the circuit tests normal, replace the ECM. Verify the scan tool TP sensor 2 voltage is greater than 4.8 volts.If less than 4.8 volts, test the signal circuit for a short to ground. If the circuit tests normal, replace the ECM. Install a 3A fused jumper wire between the signal circuit terminal D and the 5-volt reference circuit terminal E of the TP sensor 1. Verify the TP sensor 1 voltage is greater than 4.8 volts.If less than 4.8 volts, test the TP sensor 1 signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM. Install a 3A fused jumper wire between the signal circuit terminal F and the low reference circuit terminal C of the TP sensor 2. Verify that the TP sensor 2 voltage is less than 0.1 voltIf greater than 1.0 volt, test the TP sensor 2 signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM. Ignition OFF for 90 seconds, disconnect the harness connector at the ECM.Test for less than 5 ohms of resistance on all TP sensor circuits between the following terminals:ECM C2 signal circuit terminal 65 to TP terminal DECM C2 signal circuit terminal 63 to TP terminal FECM C2 5-volt reference circuit terminal 3 to terminal E If greater than 5 ohms, repair the affected circuit for open/high resistance.Test for infinite resistance between TP sensor 1 signal circuit terminal D and TP sensor signal circuit terminal F.If less than infinite resistance, repair the short between TP sensor 1 signal circuit and TP sensor 2 signal circuit. If all circuits test normal, replace the throttle body.
Fig. Throttle Actuator Control electrical connector
Throttle Body Relearn Procedure
NOTE
Do NOT perform this procedure if DTCs are set.
Start and idle the engine in PARK for 3 minutes.With a scan tool, monitor desired and actual RPM.The ECM will start to learn the new idle cells and Desired RPM should start to decrease.Ignition OFF for 60 seconds.Start and idle the engine in PARK for 3 minutes.After the 3 minute run time the engine should be idling normal.
NOTE
During the drive cycle the check engine light may come on with idle speed DTCs. If idle speed codes are set, clear codes so the ECM can continue to learn.
If the engine idle speed has not been learned the vehicle will need to be driven at speeds above 70 km/h (44 mph) with several decelerations and extended idles.
After the drive cycle, the engine should be idling normally.
If the engine idle speed has not been learned, turn OFF the ignition for 60 seconds and repeat step 6.Once the engine speed has returned to normal, clear DTCs.
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