P2293 on GMC: How to Diagnose & Fix
Fuel Pressure Regulator 2 Performance
2 GMC models · 2 documented issues · 2 critical · $8,000-$18,000 repair
P2293 on GMC by model: symptoms, diagnosis and fix
The Bosch CP4.2 high-pressure fuel injection pump used on the 2011-2016 LML (and LGH) Duramax diesel engines is prone to catastrophic failure that destroys the entire fuel injection system. Unlike its predecessor the CP3, the CP4.2 uses roller tappets riding on the cam that are lubricated only by the diesel fuel; when the fuel film is thin or the fuel is aerated, the rollers skid instead of rolling and the cam and tappet wear. When metal fatigue occurs, the pump shatters and sends metal debris throughout the entire high-pressure fuel system — contaminating all eight injectors, the fuel rails, return lines, and feed lines. Total repair cost runs $8,000-18,000. A class action lawsuit (Chapman v. General Motors) was filed against GM over 2011-2016 Silverado/Sierra HD Duramax trucks and was settled for owners who bought in seven states (CA, FL, IL, IA, NY, PA, TX). The same pump also fails in the Ford 6.7 Power Stroke (2011+) and the 2019-2020 Ram 6.7 Cummins.
Common Symptoms
- Hard start or no-start condition
- Sudden loss of power under load
- Rough running or misfiring on multiple cylinders
- Metal shavings or debris visible in fuel filter
- Fuel rail pressure codes (P0087, P0191)
- White or black smoke from exhaust
- DIC message: Reduced Engine Power
How to Fix
Replace the entire high-pressure fuel system: CP4 pump, all 8 injectors, both fuel rails, return lines, and flush the lift pump/FASS system. Install an aftermarket CP3 conversion kit (Fleece FPE-LML-CP3-WP for 2011-2016 LML) to replace the CP4.2 with the more durable CP3 design. Add a FASS or AirDog lift pump to improve fuel supply. Prevention: never run below 1/4 tank, use quality diesel fuel.
Sources for this issue (4)
The Sierra 3500HD Duramax LML diesel (2011-2016) uses the same Bosch CP4.2 high-pressure fuel pump as the 2500HD. The pump is prone to catastrophic failure that destroys the entire fuel injection system (all 8 injectors, fuel rails, return lines). The 3500HD is often used for heavier towing and work applications, which places more sustained load on the high-pressure fuel system and may accelerate CP4.2 wear. Total system replacement costs $10,000-18,000. A CP3 conversion kit (Fleece FPE-CP3K-LML or similar) is strongly recommended as a preventive upgrade on any high-mileage LML Sierra 3500HD. The 2017+ L5P switched to a Denso HP4 pump.
Common Symptoms
- Sudden hard start or no-start
- Loss of power under towing load
- Rough running on multiple cylinders
- Metal shavings in fuel filter
- Fuel rail pressure codes P0087, P0191
- Reduced Engine Power message
How to Fix
Replace entire fuel system on failure. Preventive CP3 conversion kit (Fleece FPE-CP3K-LML or S&S Diesel LML kit). Install FASS lift pump. Never run below 1/4 tank.
Sources for this issue (2)
P2293 code reference
General diagnostic-code context. The code alone does not confirm a cause for your vehicle; use the applicable issue card and its sources.
Frequently asked questions
What does P2293 mean on a GMC?
P2293 stands for "Fuel Pressure Regulator 2 Performance." This code means the engine computer has detected that the fuel pressure regulator 2 isn't performing as expected, so the system can't maintain the correct fuel pressure under varying conditions. On many direct-injection and high-pressure systems, regulator 2 controls the high-side fuel pressure, and the computer compares commanded pressure to what the fuel pressure sensor actually reports. When the measured pressure drifts too far from the target, it sets this performance code, which can cause hard starting, rough running, hesitation, reduced power, or stalling. Causes typically include a faulty regulator or high-pressure pump, a fuel delivery restriction, or a pressure sensor problem. On GMC it is documented across 2 models: Sierra 2500HD, Sierra 3500HD.
What are the most common causes of P2293?
The most common causes of P2293 are: Faulty fuel pressure regulator (regulator 2), Failing high-pressure fuel pump, Faulty or out-of-range fuel rail pressure sensor, Clogged fuel filter or restricted fuel supply, Weak low-pressure (lift) pump feeding the high-pressure system, Leaking fuel injector bleeding off pressure, Wiring or connector fault to the regulator/pump, Air or contamination in the fuel system. The specific cause varies by vehicle.
How much does it cost to fix P2293 on a GMC?
Published repair estimates on GMC range from $8,000 to $18,000 depending on the model and root cause. If an issue mentions a recall or campaign, check your VIN with the manufacturer or NHTSA and confirm eligibility and coverage with a dealer.
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Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.