DTC P0507 Idle Speed High. GMC Truck Sonoma Pickup

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2000 🢒 Sonoma Pickup - 2WD 🢒 DTC 🢒 DTC P0507 Idle Speed High

Engine Controls Components
IAC, EVAP Valve Controls, and Stop Lamp Switch Input w/ A/T
OBD II Symbol Description Notice
Powertrain Control Module Connector End Views
Handling ESD Sensitive Parts Notice

Circuit Description

The powertrain control module (PCM) controls the air entering into the engine with an idle air control (IAC) valve. In order to increase the idle RPM, the PCM commands the pintle inside the IAC valve away from the throttle body seat. This allows more air to bypass through the throttle blade. In order to decrease the RPM, the PCM commands the pintle towards the throttle body seat. This reduces the amount of air bypassing the throttle blade. A scan tool will read the IAC valve pintle position in counts. The higher the counts, the more air that is allowed to bypass the throttle blade.

Conditions for Running the DTC

•	DTCs P0105, P0107, P0108, P0112, P0113, P0117, P0118, P0122, P0123, P0125, P0128, P0131, P0132, P0133, P0134, P0171, P0172, P0179, P0201 P0202, P0203, P0204, P0300, P0336, P0440, P0442, P0446, P0453, P0502, P1133 and P1441 are not set

•	BARO is more than 72 kPa.

•	The engine coolant temperature ( ECT) is more than 40°C (104°F).

•	Engine has been running more than 20 seconds.

•	Battery voltage is between 10.0 volts and 17.1 volts.

•	Idle speed is more than 60 RPM above desired.

Conditions for Setting the DTC

The IAC valve reads less than 2 counts on the scan tool.

Action Taken When the DTC Sets

•	The malfunction indicator lamp (MIL) will illuminate after 2 consecutive ignition cycles in which the diagnostic runs with the malfunction present.

•	The PCM will record the operating conditions at the time that the diagnostic fails. This information will store in the Freeze Frame and Failure Records buffers.

•	A history DTC stores.

Conditions for Clearing the MIL/DTC

•	The MIL will turn OFF after 3 consecutive ignition cycles in which the diagnostic runs without a fault.

•	A history DTC will clear after 40 consecutive warm up cycles without a fault.

•	A scan tool can clear the DTCs.

Diagnostic Aids

•	Inspect the IAC valve electrical connection for proper mating.

•	Inspect the wiring harness for damage.

•	Inspect for a disconnected, cracked or cut vacuum hose.

•	Inspect for the proper installation of the crankcase ventilation valve.

•	Inspect the intake manifold and throttle body for leaks.

•	Inspect the intake manifold for cracks.

•	Refer to Rough, Unstable, or Incorrect Idle and Stalling .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

The Powertrain OBD System Check prompts you to complete some of the basic checks and to store the Freeze Frame and Failure Records data on the scan tool if applicable. This creates an electronic copy of the data captured when the malfunction occurred. The scan tool stores this data for later reference.

A normally operating IAC system will be able to extend and retract by a scan tool and change the engine idle RPM. The valve movement is verified by an engine RPM change.

Reprogram the replacement PCM and perform the Crankshaft Position System Variation Learn Procedure. Refer to the latest Techline information for PCM programming.

If no malfunctions are present at this point and no additional DTCs were set, refer to Diagnostic Aids for additional checks and information.

DTC P0507 Idle Air Control (IAC) System High RPM

Step

Action

Values

Yes

Did you perform the Powertrain On-Board Diagnostic (OBD) System Check?

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

Start the engine.
Install a scan tool.
Idle the engine at the normal operating temperature.
With the parking brake set, shift the transmission in P or N.
Turn OFF the A/C.
Command the IAC valve between the specified values with the scan tool.

Does the engine RPM change smoothly when commanded by the scan tool?

900-2,000 RPM

Go to Diagnostic Aids

Go to Step 3

Turn OFF the ignition.
Disconnect the IAC valve electrical connector.
Install the J 37027-A IAC driver.
Start the engine and attempt to lower and raise the RPM.

Does the engine RPM change smoothly when commanded by the IAC driver?

Go to Step 4

Go to Step 5

Turn OFF the ignition .
Check for the following conditions in the IAC valve high and low circuits:

•	Open circuits

•	Short to ground or voltage

Repair the circuit as necessary. Refer to Wiring Repairs in Wiring Systems.

Was a repair necessary?

Go to Step 9

Go to Step 6

Turn OFF the ignition.
Inspect for the following conditions in the IAC passage:

•	Vacuum leaks

•	Throttle plates not closing properly

Was a condition found?

Go to Step 9

Go to Step 7

Check the PCM electrical connector for poor connections.
Repair the electrical connector as necessary. Refer to Connector Repairs in Wiring Systems.

Was a repair necessary?

Go to Step 9

Go to Step 8

Replace the IAC valve. Refer to Idle Air Control Valve Replacement .

Is the action complete?

Go to Step 9

Important: The replacement PCM must be programmed.

Replace the PCM. Refer to Powertrain Control Module Replacement/Programming .

Is the action complete?

Go to Step 9

Use the scan tool in order to clear the DTCs.
Start the engine.
Idle the engine at the normal operating temperature.
Operate the vehicle within the Conditions for Setting this DTC as specified in the supporting text.

Does the scan tool indicate that this diagnostic has Ran and Passed?

Go to Step 10

Go to Step 2

Check to see if any additional DTCs are set.

Does the scan tool display any DTCs that you have not diagnosed?

Go to applicable DTC table

System OK