TGK Motorsport D4 Flex Fuel Kit

TGK Motorsport D4 Flex Fuel Kit


Regular price$499.99
Shipping calculated at checkout.

Include Flex Sensor Mount?


The TGK Motorsport D4 Flex fuel kit is a plug and play solution to adding flex fuel on Audi D4 A8/S8 4.0T Vehicles.  Use of this kit is to add the ability to run anywhere from straight gasoline to E85 Blend as well as reveal the true power potential of your setup.  Forced induction scenarios especially benefit from the use of ethanol, and these allow you to seamlessly switch between gasoline and ethanol without having to monitor your fuel content or reflash your tune.

This kit uses:

  • Continental Flex Fuel sensor.
  • Sensor Bracket to mount the sensor.
  • Plug and Play wiring harness made with OEM connectors and terminals crimped with OEM tooling, as well as resistor inline already preinstalled.  Harness also has a secondary output if you want to add a secondary ethanol content gauge.
  • PFTE Lined braided lines
  • All brackets included for install.
  • GT150 Terminal already installed.

PLEASE NOTE: It is possible to install this kit without tuning, but to gain the most out of the kit, as well as to automatically mix blends, the kit and harness is mainly setup to use Dyno Spectrum Tuning DS1.


  • 2009 - 2017 Audi A8
  • 2010 - 2017 Audi A8L
  • 2012 - 2018 Audi S8

Install Instructions are for a C7. Follow same instructions for a D4.  Only main hardware difference is the 90 Degree Fitting mounts to the car fitting.


Customer Reviews

Based on 1 review
Alex Palenow
Not fully developed for S8

Line to the driver side hpfp is too short, the line for the passenger side hpfp is too long. OBD2 signal cable has a too big connector pin and somehow came with a crimped cable seal which had to be removed in order to fit into the OBD2 slot. The fuse tap on the positive cable is regular size instead of mini. The S8 does have only mini fuses on the driver side Dashboard, no regular size fuses. Not satisfying.