P0507: P0507 Diagnostic Guide

What this code means

P0507 means the engine idle speed may be higher than expected compared with what the PCM wants.

What the vehicle may do

The truck may idle higher than normal.
The idle may feel like it hangs or does not settle as expected.

Possible fault areas

A possible intake air concern may be involved.
Restrictions, vacuum leaks, or damage in the intake air path can be possible areas to inspect when no other codes are present.
Operating conditions such as excessive RPM in NEUTRAL, incorrect transmission gear operation, or wheel slippage may also be involved.
If related intake throttle codes are present, possible broad areas may include TACM circuitry, intake throttle plate movement, the intake throttle actuator, or PCM-related control.

Diagnostic path

Code meaning and approach

On this 6.7 Power Stroke Super Duty, P0507 means the PCM is seeing idle speed higher than expected. The truck may act like the idle hangs or stays higher than commanded. Broadly, this can point toward an intake air concern, and operating conditions like excessive RPM in NEUTRAL, incorrect transmission gear operation, or wheel slippage may also be part of what the PCM saw. The setting point to keep in mind is this: actual engine idle speed is greater than 160 RPM above the desired RPM for greater than 5 seconds.

When related intake throttle codes are present

Before treating P0507 as a stand-alone high-idle concern, look at the rest of the scan report. If the scan shows related intake throttle control codes, the diagnostic path starts by confirming that direction. If those codes are present, move into the intake throttle checks. If they are not present, do not force this path; pause, recheck the earlier diagnostic direction, and avoid guessing. On that intake throttle path, the broad areas are TACM circuitry, a binding or obstructed intake throttle plate, the intake throttle actuator, and the PCM.

Check reference voltage and signal circuit integrity

With the ignition off, disconnect the intake throttle actuator connector, then turn the ignition on and measure between C189 Pin 5 as the positive lead and C189 Pin 4 as the negative lead. The question is: Is the voltage between 4.5 V - 5.5 V? If it is, continue with the circuit checks. If it is not, pause this intake throttle actuator path and follow the appropriate earlier diagnostic direction rather than guessing. Next, with the ignition off, disconnect PCM-E and measure resistance between C189 Pin 3 and C1232E Pin 36, C189 Pin 1 and C1232E Pin 24, and C189 Pin 2 and C1232E Pin 3. The pass point is: Is the resistance less than 5 Ω? If it is not, repair the short circuit, clear PCM DTCs, and repeat the self-test.

Check for shorts to ground, voltage, and across the motor circuits

Next, check the intake throttle actuator harness for a short to ground at C189 Pin 3, C189 Pin 1, and C189 Pin 2. The pass question is: Is the resistance greater than 10000 Ω? If it fails, repair the short circuit, clear PCM DTCs, and repeat the self-test. Then, with the ignition on, check those same intake throttle actuator harness circuits for a short to voltage. If any voltage is present, repair the short circuit, clear PCM DTCs, and repeat the self-test. If no voltage is present, continue. Then, with the ignition off, check whether TACM+ and TACM- are shorted together by measuring between C189 Pin 1 as the positive lead and C189 Pin 2 as the negative lead. That check uses the same pass question: Is the resistance greater than 10000 Ω? If it fails, repair the short circuit, clear PCM DTCs, and repeat the self-test.

Check the actuator motor and look for intermittent wiring faults

After the circuit checks pass, check the internal resistance of the intake throttle actuator motor between C189 Pin 1 on the component side and C189 Pin 2 on the component side. The question is: Is the resistance between 1 Ω - 900 Ω? If it is outside that range, the supported repair is a new intake throttle actuator, then carry out Reset And Clear The Specified Function Throttle with the scan tool, clear continuous DTCs, reset emission monitors information in the PCM, and repeat the self-test. If the motor resistance is in range, reconnect PCM-E and the intake throttle actuator connector, turn the ignition on, monitor TP1_V, and work the harness in small sections from the intake throttle actuator back toward the PCM while watching for voltage spikes. If the concern shows up during the wiggle test, repair as necessary, clear PCM DTCs, and repeat the self-test.

Command the throttle and compare response

If the harness does not show an intermittent concern, check intake throttle actuator operation with the ignition on and the engine off. Monitor TP1_V and control TP_DSD, then compare the TP1_V response to the intake throttle position values for the Super Duty. The command table includes the 0% and 100% points, so you are checking whether the sensor response approximately matches the commanded movement. If it does not, the supported repair is a new intake throttle actuator, followed by Reset And Clear The Specified Function Throttle, clearing continuous DTCs, resetting emission monitors information in the PCM, and repeating the self-test. Then, with the ignition off, disconnect the charge air cooler tube from the intake throttle actuator. Turn the ignition on, command TP_DSD closed and open, and visually inspect the intake throttle plate for correct operation. If it does not operate correctly, follow that same supported intake throttle actuator repair and retest sequence.

Finish the intake throttle path at the PCM connectors

If the intake throttle actuator operates correctly, disconnect all PCM connectors and inspect them for pushed out pins and corrosion. Reconnect all PCM connectors and make sure they seat correctly, then verify whether the concern is still present. If the concern is gone, the system is operating correctly at that time, and the fault may have been caused by a loose or corroded connector. If the concern is still present on that intake throttle path, the supported direction can lead to PCM replacement and programming, except where a separate P02E1 path applies.

P0507 intake air path

Now bring it back to the target code. For P0507, use the high-idle trigger conditions to understand why the code set, then apply code priority. Before the intake air check, make sure you have the correct schematic and connector information available for the circuit. If other codes are present, diagnose those first. If P0507 is standing by itself, inspect the entire intake air system for restrictions, vacuum leaks, and damage. If you find a restriction, a vacuum leak, or damage, repair that concern as necessary. If the intake air inspection does not turn up a concern, clear the codes and repeat the self-test. Also remember, if regeneration occurs while you are diagnosing, displayed values may be biased, so let that process complete before continuing.

Takeaway

The takeaway on P0507 is simple: treat it as a high-idle clue, not an automatic parts call. Let other codes take priority, use the intake throttle checks only when the scan report points you there, inspect the full intake air path when P0507 stands alone, repair only confirmed concerns, and then verify the repair by clearing the codes and repeating the self-test. For more diagnostic training, visit stepdiagnostics.com.