Diagnostic Instructions
DTC Descriptors
DTC P0506: Idle Speed Low
DTC P0507: Idle Speed High
Circuit/System Description
The engine control module (ECM) adjusts the fuel delivery in order to control crankshaft speed at idle. The ECM monitors the engine speed and will detect an out of range idle speed for the amount of fuel that is delivered.
Conditions for Running the DTC
• | DTCs P0016, P0117, P0118, P0335, or P0336 are not set. |
• | The engine is running at idle. |
• | The engine coolant temperature (ECT) is more than 50°C (122°F). |
• | The accelerator pedal position (APP) angle is 0 percent. |
• | These DTCs run continuously. |
Conditions for Setting the DTC
P0506
The ECM detects the actual idle speed is at least 100 RPM below the desired idle speed for greater than 19 seconds.
P0507
The ECM detects the actual idle speed is at least 200 RPM above the desired idle speed for greater than 19 seconds.
Action Taken When the DTC Sets
DTCs P0506 and P0507 are Type B DTCs.
Conditions for Clearing the DTC
DTCs P0506 and P0507 are Type B DTCs.
Diagnostic Aids
Inspect for any of the following conditions:
• | A crankcase overfill can cause oil to be forced through the positive crankcase ventilation (PCV) system. |
• | An outside source that has allowed oil or fuel to enter the air induction system. |
• | An aftermarket performance kit using an external fuel source. |
Reference Information
Schematic Reference
Engine Controls Schematics
Electrical Information Reference
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Circuit/System Verification
- Engine running, compare the scan tool Desired Idle Speed parameter to the Engine Speed parameter. Both engine speed parameters should be within 50 RPM of each other.
- Elevate the engine speed in 25 RPM increments to 1,300 RPM using a scan tool. With each commanded increment, the actual Engine Speed parameter should stay within 25 RPM of the commanded speed.
⇒ | If the vehicle passes the Circuit/System Verification Test, operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records list. |
- Engine running, observe the DTC information with a scan tool. DTCs P0506 or P0506 should not set.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
Important: You must perform Circuit/System Verification before proceeding with Circuit/System Testing.
- If there are any other DTCs set, refer to
Diagnostic Trouble Code (DTC) List - Vehicle
.
- Attempt to start the engine.
- Inspect for mechanical conditions that can limit engine speed.
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.