What this code means
P0507 means the PCM may be seeing engine idle speed higher than the idle speed it is trying to achieve.
What the vehicle may do
- The vehicle may idle higher than normal.
- The idle can feel like it hangs or does not settle as expected.
- The check engine light may be on.
- Stop/start may be disabled while the code is active on equipped vehicles.
Possible fault areas
- Possible unmetered air through the PCV system or vacuum leaks.
- Possible throttle body operation or restriction concerns.
- Possible wiring, terminal, or connector concerns in related circuits.
- Possible communication or data issues that can affect idle strategy.
- Possible PCM-related concern after the earlier checks are completed.
Diagnostic path
Opening and code logic
On this Ram 1500 Classic with the 3.6 Pentastar, P0507 means the PCM sees idle speed higher than expected. In plain terms, the module is trying to control idle, but actual engine speed may be staying above the target. The driver may notice a high idle, an idle that hangs, a check engine light, and on vehicles equipped with stop/start, that feature can be disabled while this code is active. Broadly, this can involve unmetered air from the PCV system or vacuum leaks, throttle body operation, related wiring and connector issues, communication or data problems that affect the idle strategy, and in some cases the PCM side of the circuit. The logic here is a command-versus-response check: the PCM compares actual engine speed to the target idle speed. This monitor runs with the engine idling, no throttle input requested, vehicle speed equal to zero, and engine run time of more than 30.0 seconds. The code sets when engine speed is more than 200 rpm above idle speed for 30.0 seconds.
Start with the basic checks and confirm the code
Start by completing the basic pre-diagnostic troubleshooting before going into the P0507 test path. Then start the engine and operate or road test the vehicle under the same type of conditions that allow this monitor to run. Use the scan tool to read the codes and record what is present. If P0507 is active or pending, continue with this diagnostic path. If it is not active or pending, treat it as an intermittent condition and work that direction instead of forcing a failure that is not currently showing up.
Check for companion faults that change the path
Before chasing airflow or throttle hardware, look at the other recorded codes. If there are other throttle body faults, or communication or implausible data faults involving the ABS side that are active or pending, diagnose those first. Those faults can affect the idle control strategy, so do not ignore them and jump straight to parts. If those faults are not present, move on to the PCV system inspection.
Inspect the PCV system
Turn the ignition off and inspect the PCV system carefully. Look for leaks, cracked or damaged hoses or tubes, poor hose or tube connections, and a PCV valve stuck open. Any of those can let in air the PCM is not controlling, which fits a high-idle complaint. If you find a PCV system problem, repair it as necessary, then keep verification separate and confirm the repair. If the PCV system checks clean, continue to the vacuum leak check.
Check for vacuum leaks
Start the engine and inspect for vacuum leaks. While the engine is running, stay clear of the fan, pulleys, belts, and moving parts, and do not wear loose clothing. Check for internal leaks and inspect external areas that can create a vacuum leak, including vacuum supply lines, the brake booster, the purge solenoid, and engine seals. If you find a vacuum leak, repair it as necessary, then verify the repair and confirm the code stays gone. If no vacuum leak is found, move to the throttle body and ETC wiring checks.
Check throttle body operation and ETC connections
Inspect the throttle body for carbon buildup, restrictions, and a bent throttle plate. Use a straight edge for the throttle plate check. If the throttle plate does not close completely, it may be bent and the throttle body assembly needs to be replaced. With the vehicle running, perform a wiggle test on the ETC motor wiring and connections, and listen for the idle to rise. If you find a problem, or the idle fluctuates during the wiggle test, first verify good pin-to-terminal contact at the throttle body and PCM connectors. If the connectors check out and no connector problem is found, replace the throttle body assembly. Disconnect the battery when replacing the throttle body assembly. After installation, use the scan tool to run the Throttle Body Self Learn, then verify the repair. If there are no throttle body problems and the idle does not fluctuate during the wiggle test, continue to the related harness connection checks.
Inspect related harness connections
Next, with the ignition off, disconnect the PCM harness connectors, any related in-line connectors if equipped, and the related component connectors. Inspect the harness and component connectors, along with the male and female terminals. Look for improper connector installation, damaged locks, corrosion, signs of water intrusion, damaged weather seals if equipped, bent terminals, overheating from a poor connection, terminals pushed back in the cavity, spread terminals, and poor terminal tension. Repair any conditions found. Then reconnect the PCM connectors, any in-line connectors, and the related component connectors, making sure they are fully seated and the locks are fully engaged. Erase the codes with the scan tool, operate or road test the vehicle under the monitor conditions, and read the codes again.
Verification and final decision
Keep the final verification separate from the testing. After the harness connection work and retest, if P0507 returns, replace and program the PCM, then verify the repair. If the code does not return, the wiring or poor connection problem has been repaired, and the final step is still to verify the repair and confirm the code stays gone. The takeaway is simple: for P0507, prove whether the high idle is coming from uncontrolled air, throttle body operation, connector integrity, or the final PCM decision point, and do it in that order. For more diagnostic training, visit stepdiagnostics.com.
Final check
This code is often diagnosed by comparing the commanded idle strategy to the actual engine response, then checking for uncontrolled air, throttle body behavior, connection integrity, and final module-
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