2014 Jeep Wrangler JK Factory Service Manual 28 - DTC-Based Diagnostics

P0507-IDLE SPEED PERFORMANCE HIGHER THAN EXCEPTED

For a complete wiring diagram, refer to the Wiring Information.


Theory of Operation

The objective of the Idle “Speed Rationality is to monitor the ability to achieve and maintain a steady idle condition. The monitor will judge the functionality of the idle speed control system by monitoring RPM during idle. If RPM does not come within a calibrated dead band of target idle speed, a timer is started. If the timer reaches its maximum threshold without any sign of the RPM trending towards control, a soft failure is generated.


Possible Causes

AIR INDUCTION SYSTEM LEAKS
PCV SYSTEM LEAKS
ENGINE VACUUM LEAKS
THROTTLE BODY
POWERTRAIN CONTROL MODULE (PCM)

Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).


1. ACTIVE DTC



NOTE: If any other Throttle Body DTCs are present, they must be diagnosed and repaired before continuing this test.
1. Start the engine.

WARNING:

When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in possible serious or fatal injury.

2. Allow the engine to reach normal operating temperature.
3. With a scan tool, select View DTCs.

NOTE: It may be necessary to drive the vehicle to meet the conditions to set this DTC, try to repeat the conditions in which the fault originally set by reviewing the Freeze Frame data.


Is the DTC Active or Pending at this time?

Yes


No


2. AIR INDUCTION SYSTEM

1. Inspect the Air Induction System for the following problems.
2. Leaks: Air Intake tube connection, Air Cleaner housing, etc.


Were any problems found?

Yes


No


3. PCV SYSTEM

1. Inspect the PCV system for the following problems:
2. Leaks - cracked or damaged hoses or tubes, poor hose or tube connections, PCV valve stuck open, etc.


Were any problems found?

Yes


No


4. VACUUM LEAKS

WARNING:

When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in possible serious or fatal injury.

1. Start the engine.
2. Inspect the vehicle for external vacuum leaks.
3. Inspect the engine for internal leaks.


Were any vacuum leaks found?

Yes


No


5. THROTTLE BODY OPERATION

1. Inspect the throttle body for carbon build up, other restrictions, and a bent throttle plate using a straight edge.
2. If the throttle plate does not close entirely it may be bent and needs to be replaced.

WARNING:

When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in possible serious or fatal injury.

3. While the vehicle is running, lightly tap on ETC Motor where applicable, with your hand, and listen for idle to raise.


Were any problems found or did the idle fluctuate while tapping on the ETC Motor?

Yes


No


6. POWERTRAIN CONTROL MODULE (PCM)

1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Throttle Body and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Throttle Body and Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.


Were there any problems found?

Yes


No