Fix P2111: Mechanic’s solutions that WORKED

The code P2111: Throttle Actuator Control System – Stuck Open points out a fault in the Throttle Actuator Control System, indicating it’s stuck open, and is most likely caused by a mechanical obstruction or an electrical malfunction within the throttle body or its control system.

P2111 quick overview

Meaning	P2111: Throttle Actuator Control System – Stuck Open
Is it serious?	This code is quite serious as it can affect your vehicle’s drivability, potentially leading to situations where the car unexpectedly accelerates or fails to respond correctly.
Possible causes	– Faulty or stuck open throttle body – Obstruction in the throttle mechanism – Electrical issues with the throttle actuator control system – Damaged or disconnected wiring to the throttle body – Poor connections or shorts in the throttle body’s circuit
How to diagnose?	Inspect Throttle Body: Check for physical blockages, damage, or signs of wear. Check Wiring and Connectors: Examine all related wiring and connectors for damage, disconnections, or corrosion. Perform Throttle Relearn: After cleaning or replacing parts, conduct a throttle relearn procedure. Check for Recalls: Verify if there are any manufacturer recalls for your vehicle’s throttle system. Use Proper Diagnostic Tools: Ensure accurate diagnosis with a compatible and comprehensive scan tool. Consult Technical Literature: Refer to your vehicle’s service manual for specific diagnostic procedures.

How to fix P2111 – learn from mechanics

I looked into P2111 service cases at iatn.com website where in the private forums the mechanics seek advice from other mechanics. I looked up a bunch of cases to help you decide how to fix your issue and see what would a real mechanic do to solve it.

Case #1: Ford

Vehicle Information:
2005 Ford E-450 Super Duty 6.8L

Issue + Repair History:

• Vehicle was running poorly with the MIL Lamp on.
• Technician unable to find repair information for the present codes.

Other OBD2 Codes + Test Results:

• P2104: Throttle Actuator Control System Forced Idle
• P2112: Actuator System Stuck Closed
• P2111: Actuator System Stuck Open

Suggestions to Fix Issue:

• Check the fly-by-wire throttle system, particularly the pedal assembly.
• Test circuits in the Throttle Actuator Control (TAC) system.
• Ensure continuity through the wiring harness to the throttle pedal sensor from the PCM and from the throttle actuator assembly to the PCM.
• Consider replacing the throttle body if wiring and connections are good.

Final Fix:

• After cleaning connections on the TAC system and clearing codes, the problem was temporarily resolved.
• If the issue reoccurs, the technician believes replacing the throttle housing due to slop in throttle plate shaft may be necessary.

Case #2: Ford

Vehicle Information:
2010 Ford Explorer 4.0L

Issue + Repair History:

• Came in with codes P2104 and P2111, indicating throttle issues.
• Initially unable to duplicate the condition; the issue happened only once to the customer.
• A new OEM throttle body was installed based on previous issues noted with the throttle body and TPS.

Other OBD2 Codes + Test Results:

• P2104: Throttle Actuator Control System – Forced Idle
• P2111: Throttle Actuator Control System – Stuck Open

Suggestions to Fix Issue:

• Check for misfires and bad coils as they can cause these DTCs.
• Ensure the throttle body is OE and consider if a PCM reflash is available for these codes.
• Inspect the air box, MAF sensor for contaminants, and check for a bad alternator or coil pack throwing off RF.
• Tighten spring pins in the connector that connects the TPS for a better grip and connection.

Final Fix:

• The vehicle began acting up more consistently when hot, with dropouts observed in the TPS2 data via the IDS.
• The wiring harness near the EGR valve was found rubbed through, barely exposing the TPS2 signal wire, causing intermittent grounding.
• Repairing the wire and rerouting the harness away from the EGR valve resolved the issue.

Case #3: Dodge

Vehicle Information:
2003 Dodge Ram 2500 5.7L

Issue + Repair History:

• Towed to the shop with complaints of no power and no change on acceleration.
• Multiple codes were retrieved related to throttle and sensor issues.
• Throttle relearn procedure attempted but not completed.
• 5V supply from PCM to sensors was lower than expected.

Other OBD2 Codes + Test Results:

• PO123: TPS/APPS Circuit High
• PO223: APPS Signal #2 Voltage is Too High
• P2111: Electronic Throttle Control (ETC) Unable to Close
• P2106: Electronic Throttle Control System Forced Limited Power
• 5V supply check to both APPS and ETC sensor showed 4.73V, below the expected range.

Suggestions to Fix Issue:

• Check for inactive throttle body due to cold ambient temperatures.
• Ensure the reference voltage should be between 4.9-5.1 volts and unplug all 5-volt sensors one at a time to pinpoint the issue.
• Look for a split intake that might generate codes due to a vacuum leak.
• Consider the effects of cold on the EGR valve, which might impact the 5V signal.

Final Fix:

• Multiple issues were found and resolved: a broken lower intake manifold and an APP sensor shorted to ground.
• A computer relearn was performed with a factory scanner, and the 5V reference was rechecked to be 4.96V.
• After repairs, the truck ran well.

Case #4: Chrysler

Vehicle Information:
2006 Chrysler 300 C 5.7L

Issue + Repair History:

• Initially reported no power and did not change on acceleration.
• Multiple codes were found including P1411 for Cylinder #1.
• Found bent #1 intake push rod, replaced but still no compression and tapping noise.
• After resetting parameters, the car would start then cut out, introducing new codes.

Other OBD2 Codes + Test Results:

• P0688: ASD Relay
• P2101: Throttle Body
• P2111: Electronic Throttle Control Unable to Close
• P1411: MDS #1

Suggestions to Fix Issue:

• Check if the vehicle is in theft mode as it could cut off fuel.
• Use the correct scan tool, as DRB3 might not be adequate for comprehensive diagnostics.
• Restore compression and check EGR operation, valve springs, and for vacuum leaks before addressing throttle issues.
• Consider fuel issues if the car runs when manually introducing fuel.

Final Fix:

• The issue was resolved by finding and repairing a bad connection under fuse #13, which was discovered while checking fuses.
• After the repair, the car started, learned the throttle body position, and ran on all 8 cylinders.

Case #5: Volvo

Vehicle Information:
2004 Volvo S60 2.5T AWD 2.5L

Issue + Repair History:

• Vehicle constantly in limp mode with very rough idle.
• Pulled code 91b7 related to the throttle valve.
• Cleaned throttle plate and performed resistance test of throttle motor, but symptoms persisted.
• After resetting, the vehicle wouldn’t start properly, running for a second before dying.

Other OBD2 Codes + Test Results:

• P2111: Volvo code # 91b7 – Throttle valve
• Checked 5V supply to sensors and scoped both throttle position sensors, both showing a clean sweep.

Suggestions to Fix Issue:

• Check for recalls on the throttle body as it’s a known issue for this model.
• Perform a wiggle test and terminal drag tests at the ECM and throttle body to check for intermittent open/short circuits.
• Check the MAF air flow measurement to ensure it’s within the normal range.
• If all wiring and connections are verified, consider replacing the throttle unit.

Final Fix:

• The vehicle eventually stopped acting up.
• Replaced the throttle body with a used unit and cleaned it.
• Added stabilant to the throttle connections and ECM connections.
• After a full day of test driving and a week with the customer, the issue was resolved.

Advice	Diagnostic Step Description
Check for Recalls	Verify if there are any recalls related to the throttle body or associated components for your specific vehicle.
Clean Throttle Body	Remove and thoroughly clean the throttle body, focusing on the plate and housing.
Inspect Wiring and Connections	Perform terminal drag tests, check for shorts, opens, and ensure all connections are secure and clean.
Replace Throttle Body	If diagnostics and cleaning don’t resolve the issue, consider replacing the throttle body.
Check Grounds and Power Feeds	Ensure all ECM grounds are secure and that power feeds have no voltage drop.
Perform a Throttle Relearn Procedure	After any repair or replacement, conduct a throttle relearn procedure to ensure proper calibration.
Use Proper Diagnostic Tools	Utilize the correct scan tool that is compatible with your vehicle for accurate diagnostics.
Check Other Related Components (MAF, EGR, Coils, etc.)	Inspect related systems that might affect throttle body performance, like the MAF sensor or EGR valve.