P2119 on 2015-2018 Chevrolet Colorado: Throttle Body Performance Fixes

What's Unique About the 2015-2018 Chevrolet COLORADO

For the 2015-2018 Colorado, this code is often triggered by simple carbon and gunk buildup inside the throttle body, a common issue on many modern drive-by-wire vehicles, especially those with direct-injection engines like the 3.6L V6. General Motors has issued technical service bulletins for this exact issue. TSB #PIE0444A was an engineering request to gather data on P2119 and P2101, asking technicians to first check for simple issues like loose connections before replacing parts. Another bulletin, #PIP5513, clarifies that P2119 alone should not trigger a check engine light and advises against replacing the throttle body unless other diagnostic codes point to it as the definitive cause.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Check Engine Light is on
• Vehicle enters 'Reduced Power' or 'Limp Mode'
• Slow or delayed throttle response
• Unstable, rough, or surging idle
• Engine may stall at low speeds or when stopping
• Poor acceleration
• Unexpected automatic transmission shift points

Most Likely Causes

1. Dirty Throttle Body 🔴 High Probability → Shop Fuel Injection Throttle Body The direct-injection engines used in these trucks allow oil vapors and carbon from the PCV system to bake onto the throttle plate and bore. This buildup creates a sticky residue that physically prevents the spring-loaded throttle plate from closing quickly and correctly.
   How to confirm: Remove the air intake duct from the throttle body and visually inspect for a black, tar-like buildup on the metal throttle plate and surrounding surfaces. Manually push the plate open (with the engine off) to see if it feels sticky or returns slowly.
   Typical fix: Thoroughly clean the throttle body plate and bore using a dedicated throttle body cleaner and a soft cloth or toothbrush. 🎬 Watch: How to clean your throttle body to fix code P2119. Do not spray directly into the electronic components. After cleaning and reassembly, a throttle relearn procedure is mandatory to restore a stable idle.
   Est. part cost: $10-$20
2. Failing Throttle Body Assembly 🟡 Medium Probability → Shop Fuel Injection Throttle Body The internal electronic motor or the integrated throttle position sensors (TPS) can fail from heat cycles and wear, leading to erratic operation or a complete loss of control.
   How to confirm: If cleaning the throttle body does not resolve the code (or it returns quickly), and the wiring is confirmed to be good, the assembly itself is the likely culprit. An advanced scan tool can monitor 'Commanded Throttle Position' vs. 'Actual Throttle Position' to spot discrepancies in live data, confirming the failure.
   Typical fix: Replace the entire throttle body assembly. 🎬 See this step-by-step walkthrough for replacing the throttle body assembly. This part requires a throttle relearn procedure to be performed with a scan tool or via a manual process for the engine to idle and run correctly.
   Est. part cost: $150-$400
3. Wiring or Connector Issue ⚪ Low Probability Vibrations and heat can damage the wiring harness. Some owners have reported that corroded main ground connections in the engine bay can cause a host of random electrical faults, including throttle-related codes. TSB PIE0444A also specifically advises checking for a poorly seated connector at the throttle body.
   How to confirm: Visually inspect the wiring harness leading to the throttle body for chafing, melting, or damage. Disconnect the connector and check for corrosion or bent pins. Specifically, locate and inspect the main chassis ground points on the fenders near the air filter box for corrosion.
   Typical fix: Repair the damaged section of wiring, clean/replace the electrical connector, or clean and re-secure the main ground connections.
   Est. part cost: $5-$50

Rare But Worth Checking

• Faulty Powertrain Control Module (PCM): This is extremely rare. Before considering PCM replacement, all other possibilities, including the throttle body, wiring, grounds, and other related sensors, must be exhaustively ruled out.

Diagnosis Steps

1. Read all trouble codes with an OBD-II scanner. Note P2119 and any other codes present, especially P2101, as they are key to the diagnosis.
2. Per TSB PIE0444A, first check that the air intake duct is properly secured to the throttle body.
3. Inspect the electrical connector at the throttle body. Ensure it is fully seated and free of corrosion or damaged pins.
4. Inspect the main engine ground connections on the inner fenders for corrosion, a known issue that can cause phantom electrical problems.
5. Remove the air intake duct. Visually inspect the throttle plate and bore for heavy carbon buildup. Manually check if the plate moves freely and snaps back to its resting position.
6. If dirty, disconnect the battery, remove the throttle body for safety, and clean it thoroughly with dedicated throttle body cleaner and a soft cloth/brush.
7. Reinstall the throttle body, reconnect the battery, and perform the specific Throttle Relearn Procedure detailed below. Do not skip this step.
8. If the code returns after cleaning and a successful relearn, the issue is likely a faulty throttle body assembly that needs replacement.
9. An advanced scan tool can confirm a bad throttle body by commanding throttle positions and observing if the actual position reported by the sensors matches the command.

Parts You'll Likely Need

• Throttle Body Assembly (3.6L V6) (OEM #12670981) — If cleaning fails to resolve the sticky or unresponsive throttle plate, the entire unit, which contains the non-serviceable motor and sensors, must be replaced. This is for the V6 engine.
  Trusted brands: ACDelco, GM Genuine Parts, Dorman, Standard Motor Products (SMP)
  OEM price range: $200-$400
  Aftermarket price range: $150-$250
• Throttle Body Assembly (2.5L I4) (OEM #12670839) — This is the corresponding replacement part for the 4-cylinder engine, used when cleaning does not fix the code.
  Trusted brands: ACDelco, GM Genuine Parts, SKP, Hitachi
  OEM price range: $190-$380
  Aftermarket price range: $120-$220
• Throttle Body Cleaner — This is the first and most crucial part for the most common fix, which is cleaning the carbon buildup that causes the P2119 code.
  Trusted brands: CRC, Berryman, Gumout
  Aftermarket price range: $10-$20

Related Codes That Often Appear With This One

• P2101 — P2101 ('Throttle Actuator Position Performance') is very often seen with P2119. TSB PIE0444A explicitly links these two codes, as both relate to the throttle actuator's performance and are often triggered by the same root cause.
• P0506 / P0507 — These codes for 'Idle Air Control System RPM Lower/Higher Than Expected' can appear after cleaning or replacing a throttle body if the mandatory idle relearn procedure is not performed correctly.

Technical Service Bulletins (TSBs) & Recalls

• PIE0444A: 'Engineering Information — Malfunction Indicator Lamp Illuminated with DTCs P2101 Throttle Actuator Position Performance and/or P2119 Throttle Closed Position Performance.' This bulletin is for data gathering and advises checking basic connections before escalating repairs.
• PIP5513C: 'Diagnostic Tip For Malfunction Indicator Lamp (MIL) Illuminated With DTC P2119 Set'. This bulletin clarifies P2119 is a secondary code and does not warrant throttle body replacement on its own. Diagnosis should focus on other active DTCs.

Platform-Specific Known Issues

• A GM Engineering Information bulletin, #PIE0444A, was issued for the 2017-2018 Colorado/Canyon with the 3.6L LGZ engine. It directs technicians to gather data on vehicles with DTCs P2101 and/or P2119 before performing repairs, and to check simple things first like the air duct connection, electrical connector, and throttle blade movement by hand.
• GM document PIP5513C explicitly states that P2119 is a 'Type C' code that will not illuminate the MIL or cause reduced power *by itself*. It strongly advises technicians *not* to replace the throttle body for P2119 alone, but to diagnose the other codes that are present and causing the drivability concern.

Mechanic-Grade Diagnostic Values

• Throttle Position Sensor (TPS) Voltage — expected: Two opposing signals. One should sweep smoothly from low to high voltage (e.g., ~0.5V to ~4.5V), while the second sweeps from high to low (e.g., ~4.5V to ~0.5V) as the throttle plate is opened manually.. Failure: Any gaps, spikes, or flat lines in the voltage sweep indicate a failing sensor.
• Throttle Actuator Control (TAC) System Voltage Supply — expected: 11.5V – 13.5V with the engine running.. Failure: Persistent low voltage (<11.5V) suggests a problem with the battery, alternator, or a corroded ground/power connection, which can trigger a false P2119.
• Wiring Harness Continuity — expected: ≤ 0.5 Ω on signal and reference wires between the PCM and the throttle body connector.. Failure: High resistance (OL or significantly > 0.5 Ω) indicates a break or corrosion in the wire that needs to be repaired.

Scan Tool Commands That Help

• GDS2 / Professional Scan Tool: Throttle Actuator Test (Bi-Directional Control) — Use this to command the throttle plate to open and close while observing its movement. This helps determine if the failure is in the throttle motor itself or if the plate is physically sticking due to carbon buildup.
• GDS2 / Professional Scan Tool: Idle Learn / Throttle Position Learn Reset — This is a mandatory procedure after cleaning or replacing the throttle body. The function resets the learned idle values in the ECM. Failure to perform this step will almost certainly result in an unstable idle and new trouble codes like P0506 or P0507.

Wiring & Ground Locations

• G105 / SP106 — On the passenger side inner fender in the engine compartment, typically located behind the engine air filter box.. This is a major ground splice pack for numerous engine bay components. Corrosion here is a well-documented issue that can cause intermittent and difficult-to-diagnose electrical faults, including insufficient voltage or erratic signals for the throttle control system.
• G100 / SP105 — On the driver's side inner fender in the engine compartment, typically near the battery and underhood fuse block.. This is the other primary engine bay ground splice pack. Like G105, corrosion here can disrupt the proper function of the EBCM and other modules that interface with the throttle control system.
• Throttle Body Connector — Directly on the electronic throttle body assembly.. This 6-pin connector provides all power, ground, and signal lines to the throttle body. TSB PIE0444A specifically calls out checking for a poorly seated connector. The pigtail harness uses 20-gauge wires and can be susceptible to damage from heat and vibration.

OEM Part Supersession History

• 12632172, 12648415, 12669016, 12671015 → 12670981 — Part consolidation and design updates by the manufacturer.
  Heads up: The newest part number, 12670981, is the correct replacement for the 3.6L V6 and supersedes all previous versions.
• 12627217, 12669073 → 12670839 — Part consolidation and design updates by the manufacturer.
  Heads up: The newest part number, 12670839, is the correct replacement for the 2.5L I4 and supersedes previous versions.

Model Year Variations Within This Range

• 2017-2018: The 3.6L V6 engine was updated from the LFX to the LGZ engine in 2017. GM Technical Service Bulletin PIE0444A, which specifically investigates codes P2101 and P2119, is targeted at the 2017-2018 models with the LGZ engine.