SMG 2016+ CTS-V (LT4) Flex Fuel Kit V3

SMG Flex Fuel Conversion Kit – V3 Redesigned Edition

SMG’s Flex Fuel Conversion Kits are the benchmark for clean, reliable, and performance-oriented flex fuel integration. Every kit is 100% plug-and-play — no cutting, splicing, or guesswork required. We use only high-quality OEM-style electrical connectors, and each harness is wrapped in a continuous flexible braid for lasting durability and a professional, OEM-plus appearance.

The redesigned V3 kit is shown in the updated product photos, including assembled, component, and installed views.

Performance You Can Feel

With minimal tools and roughly 30 minutes of installation time (depending on mechanical experience), you can equip your vehicle with the capability to safely run high-octane ethanol fuels.
With proper tuning, many modern engines have seen gains exceeding 30 wheel horsepower — making this one of the most powerful dollar-for-dollar upgrades available.

No other simple bolt-on delivers this kind of performance, reliability, and visual appeal.

Installation Details

• Fully plug-and-play harness – no wire cutting or fuel line modification required

• 100% reversible installation

• Underhood mounting connects directly at your OEM fuel rails

   

   

Installation guides may be available for reference, but SMG does not provide installation or tuning support. Consult a professional installer or tuner if attempting a DIY install.
If your vehicle doesn’t have a vehicle-specific guide, a Universal PCM Pin-Out Reference is available for general wiring assistance.

PCM signal-wire connection: Download the SMG Flex Fuel PCM Pinout Guide V5.0 (PDF). Identify your installed controller and connector before pinning; coverage and calibration requirements are listed in the guide.

Sensor not reading? Download the SMG Flex Fuel Kit Troubleshooting Guide (PDF) for PCM pinning, connection checks, HP Tuners setup, diagnostic codes and warranty bench-testing/RMA instructions.

Warranty & Professional Installation

Professional installation is required for warranty validation.
While performance parts typically do not include a warranty, SMG stands behind our craftsmanship — if your kit is installed by a verifiable professional, we’ll cover SMG in-house components for life (to the original purchaser).
All claims require return and testing by SMG before any authorization is issued.

Additional Notes

• Current product version: V3, as shown in the product photos.

• Tune required to enable ethanol sensor functionality and run ethanol fuels.