Idle Speed Performance
P0221 - IDLE SPEED PERFORMANCE
When Monitored and Set Condition
- When Monitored: With the engine running.
- Set Condition: Low limit: The Powertrain Control Module (PCM) required engine RPM must be reached within 25 seconds. The fault is set if the engine RPM is less than the PCM required RPM by 100 RPM or more after 25 seconds. High limit: The PCM required engine RPM must be reached within 25 seconds. The fault is set if the engine RPM is greater than the PCM required RPM by 200 RPM or more after 25 seconds.
Diagnostic Test
1. PRE-DIAGNOSTIC CHECK OUT
NOTE: Always perform diagnostics with a fully charged battery.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.
NOTE: Check for applicable TSBs related to the problem.
Turn the ignition on.
With the DRB III(R), read PCM DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors. Repair as necessary.
Perform this procedure prior to symptom diagnosis.
Continue
- Go To 2
2. CHECK FOR CURRENT DTC
NOTE: Diagnose and repair any Throttle Body or Accelerator Pedal Position Sensor (APPS) DTC before diagnosing this DTC.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.
NOTE: Check for any Technical Service Bulletins that may apply.
NOTE: If the PCM detects and stores a DTC, the PCM also stores the engine/vehicle operating conditions under which the DTC was set. Some of these conditions are displayed on the DRB III(R) at the same time the DTC is displayed.
NOTE: Before erasing stored DTCs, record these conditions. Attempting to duplicate these conditions may assist when checking for a DTC.
Turn the ignition on.
With the DRB III(R), erase PCM DTCs.
NOTE: It maybe necessary to road test the vehicle for this DTC to set.
With the DRB III(R), read PCM DTCs.
Did this DTC set again?
Yes
- Go To 3
No
- Go To 7
3. AIR INTAKE SYSTEM
Turn the ignition off.
Inspect the Air Intake System for the following problems.
Restrictions: Dirty Air Cleaner, Foreign material trapped in the air intake tube, etc.
Leaks: Air Intake tube connection, Air Cleaner housing, etc.
Remove the Air Cleaner Housing and MAF Sensor from the Throttle Body.
Check for any signs of a foreign material causing the Throttle to remain open.
Were any problems found?
Yes
- Repair or replace as necessary.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
No
- Go To 4
4. VACUUM LEAKS
Start the engine.
Inspect the vehicle for external vacuum leaks.
Inspect the engine for internal leaks.
Were any vacuum leaks found?
Yes
- Repair the vacuum leak as necessary.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
No
- Go To 5
5. THROTTLE BODY OPERATION
Turn the ignition off.
Inspect the throttle body plate for carbon build up or other restrictions.
Verify that the Accelerator Pedal and APPS are not binding.
WARNING: WHEN THE ENGINE IS OPERATING, DO NOT STAND IN A DIRECT LINE WITH THE FAN. DO NOT PUT YOUR HANDS NEAR THE PULLEYS, BELTS OR FAN. DO NOT WEAR LOOSE CLOTHING.
While the vehicle is running, lightly tap on the ETC Motor with your hand and listen for the idle to raise.
Were any problems found?
Yes
- Repair or replace as necessary.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
No
- Go To 6
6. PCM
NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.
If there are no possible causes remaining, view repair.
Repair
- Replace and program the Powertrain Control Module.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
7. INTERMITTENT WIRING AND CONNECTORS
The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.
NOTE: Check connectors - Clean/repair as necessary. Poor pin to terminal connections can set DTCs.
Using the wiring diagram/schematic as a guide, inspect the wiring and connectors specific to this DTC. Wiggle the wires while checking for shorts and open circuits.
NOTE: Check for any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform POWERTRAIN VERIFICATION TEST - VER 2. Powertrain Verification Test - Ver 2
No
- The condition that caused this DTC to set is currently not present. Inspect the related wiring harness for a possible intermittent condition.