P1467 on 2019-2020 GMC Sierra 1500 2.7L: EVAP Purge Pump Causes and Fixes

What's Unique About the 2019-2020 Gmc SIERRA 1500

For this specific generation of Sierra with the 2.7L Turbo engine, the P1467 code became a widely known issue shortly after launch. GM first identified it as a software anomaly causing false codes, issuing a technical service bulletin (19-NA-148) to reprogram the computer. Soon after, they also acknowledged a high failure rate of the physical EVAP purge pump itself, leading to a generous Special Coverage program (N202324990) that extends the warranty on this specific part to 15 years or 150,000 miles. 🎬 Watch: Why your truck might set the P1467 code An early engineering bulletin, PIE0544A, also shows GM was investigating the root cause from the beginning.

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 (Malfunction Indicator Lamp) is illuminated.
• No noticeable drivability issues in most cases.
• Receiving a diagnostic alert text from OnStar to service the emissions system.

Most Likely Causes

1. ECM Software Anomaly 🔴 High Probability Early versions of the ECM software for the 2.7L engine were overly sensitive or contained a bug that could incorrectly set this code. GM issued TSB 19-NA-148 to address this specific problem, stating the cause may be a "software anomaly".
   How to confirm: A GM dealership or a shop with access to GM's service information system can check the vehicle's current software calibration level against the latest version. The TSB instructs technicians to verify if the ECM has the latest software; if not, they are to reprogram it.
   Typical fix: Reprogram the Engine Control Module (ECM) with the updated software. This is a dealer-only procedure that requires a stable voltage supply during the update.
   Est. part cost: $0
2. Failed EVAP Purge Pump 🔴 High Probability The EVAP purge pump used on these models has a known high failure rate, prompting GM to issue Special Coverage N202324990. An updated pump and canister were released to correct the concern, which could be caused by overfilling the fuel tank.
   How to confirm: If the ECM software is up to date and the code returns, the purge pump is the likely culprit. A technician can use a scan tool to command the pump on and monitor its response to confirm failure. Special Coverage N202324990 explicitly directs dealers to check for code P1467 and proceed with replacement if found.
   Typical fix: Replace the EVAP purge pump. This repair is covered by GM Special Coverage N202324990 for 15 years/150,000 miles. The OEM part number is 12690568, which has been superseded by part number 12741163.
   Est. part cost: $80-$150

Rare But Worth Checking

• Wiring Harness Issue: While less common for this specific code (TSB 19-NA-148 explicitly rules it out in many cases), damage to the wiring or connector for the EVAP purge pump can still occur. TSB 21-NA-149 notes a potential for the engine harness to chafe on the ECM/TCM bracket, upper control arm, or shock tower on 2.7L L3B engines, which could cause various electrical issues.

Diagnosis Steps

1. First, contact a GMC dealership with your Vehicle Identification Number (VIN). Ask them to check if your truck is covered under Special Coverage N202324990 or TSB 19-NA-148.
2. If covered, schedule a service appointment. The dealer will follow GM's diagnostic procedure, which will likely be free of charge.
3. If not covered or diagnosing yourself, use a scan tool to confirm P1467 is the only code present. Note if P1469 is also present.
4. Visually inspect the EVAP purge pump and its electrical connector for any signs of damage or corrosion. The pump is located on the driver's side of the engine, near the intake manifold, and is a small black plastic assembly with three bolts and two hose connections.
5. Inspect the engine wiring harness for chafing, particularly near the ECM/TCM bracket, the driver's side upper control arm, shock tower, camshaft carrier cover, and generator bracket, as noted in TSB 21-NA-149.
6. If a capable scan tool is available, command the EVAP purge pump to run and monitor its speed parameter. If it fails to run or runs below specification, the pump is likely faulty.
7. If the pump and wiring appear okay, the issue may be the ECM software. This requires a dealer visit to confirm the software version and perform an update if necessary per TSB 19-NA-148.

Parts You'll Likely Need

• Evaporative Emission Canister Purge Pump (OEM #12741163 (supersedes 12690568)) — This part has a high failure rate on these trucks and is the subject of a GM Special Coverage program. If the ECM software is current, this is the most likely failed component. The original part may have been susceptible to liquid fuel intrusion.
  Trusted brands: ACDelco (GM Genuine)
  OEM price range: $100-$175
  Aftermarket price range: $80-$120

Related Codes That Often Appear With This One

• P1469: A related EVAP code that may be set due to the same cause (liquid fuel in the purge pump from over-filling the tank).

Technical Service Bulletins (TSBs) & Recalls

• 19-NA-148: Addresses a software anomaly causing P1467 and instructs dealers to reprogram the ECM.
• PIE0544A: An early engineering request for information on vehicles with DTC P1467 to investigate the root cause.
• N202324990: Special Coverage program extending the warranty on the EVAP purge pump to 15 years/150,000 miles.
• N232395310: A similar special coverage for 2021 models that also mentions checking the canister for liquid fuel.
• 21-NA-149: Details a potential engine wiring harness chafe condition on the 2.7L L3B that could cause various electrical faults.
• PIT5723: A preliminary bulletin indicating that overfilling the fuel tank can cause liquid fuel to saturate the EVAP purge pump.

Platform-Specific Known Issues

• Special Coverage N202324990: GM has extended the warranty for the EVAP purge pump on certain 2019-2020 Sierra 1500s with 4-cylinder gas engines. The coverage lasts for 15 years or 150,000 miles, whichever comes first. If the pump fails and sets code P1467, a GM dealer will replace it at no charge.
• TSB 19-NA-148: This technical service bulletin addresses a software anomaly that can cause DTC P1467 to set. The fix is to reprogram the Engine Control Module (ECM) with updated software.
• TSB PIE0544A: This was an early engineering bulletin where GM requested information from dealers on vehicles setting code P1467 to help determine the root cause, indicating this was a known issue early in the vehicle's life cycle.
• Potential for Fuel Intrusion: An engineering bulletin (PIT5723) suggests that over-filling the fuel tank can cause liquid fuel to enter and damage the EVAP purge pump, leading to code P1467.

Scan Tool Commands That Help

• GDS2 / Professional Scan Tool: EVAP System Test / Output Controls — To functionally test a suspected bad EVAP purge pump after confirming software is up to date. With the engine running, command the EVAP Purge Pump OFF and the EVAP Canister Vent Valve ON (which closes it). Monitor the Fuel Tank Pressure (FTP) sensor data. If the pressure begins to drop (indicating a vacuum is being pulled), it confirms the purge pump is stuck open or leaking internally, as it should be sealed when commanded off.

Wiring & Ground Locations

• Engine Harness Chafe Points (TSB 21-NA-149) — On 2.7L L3B engines, inspect the engine wiring harness for rubbing/damage at: the ECM/TCM bracket, driver-side upper control arm, the shock tower bolt, across the top of the camshaft carrier cover, and at the generator bracket.. While TSB 19-NA-148 suggests P1467 is not typically a wiring issue, TSB 21-NA-149 identifies multiple known chafe points on the 2.7L engine harness that can cause a wide variety of electrical faults. A short or open in the purge pump circuit could theoretically set this code, making a harness inspection a critical step if the pump and software are known-good.
• G103 (Ground) — Located on the front of the passenger side cylinder head.. This is a key ground point for the engine's control systems. GM bulletin PIE0548 investigated issues from loose connections at this ground. A poor ground can cause erratic voltage and unpredictable behavior from sensors and actuators, including the EVAP purge pump, potentially leading to under-speed or other performance codes.

Real Owner Repair Stories

• Reddit user in r/Tucson (2019 Chevy Silverado 1500 4-cyl) — Check engine light with code P1467 (evap purge pump underspeed) and a second code for a crankshaft sensor.
  ✅ What actually fixed it The user was in the process of taking the vehicle to a dealer for the repair under the extended warranty (Special Coverage). The key takeaway was their concern about the dealer charging a $180 diagnostic fee if the issue was not the covered part, highlighting a common owner concern when dealing with warranty repairs for this specific code.

OEM Part Supersession History

• 12690568 (and others, like 12734328) → 12741163 — The original EVAP purge pumps had a high failure rate, leading to the P1467 code. The updated part 12741163 is the official replacement used for repairs under GM's Special Coverage programs (like N202324990) to provide a more durable solution.