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COBB Tuning Flex Fuel Ethanol Sensor Kit 3 Pin - Subaru STi 2004-2006 / WRX 2006-2007

COBB Tuning Flex Fuel Ethanol Sensor Kit 3 Pin

Subaru STi 2004-2006 / WRX 2006-2007

COBB Tuning Flex Fuel Ethanol Sensor Kit 3 Pin - Subaru STi 2004-2006 / WRX 2006-2007
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Part # 312550

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Features & Product Details

The COBB Tuning 3 Pin Flex Fuel and Ethanol Sensor Kit will allow users to safely convert their fuel systems to properly run ethanol. Why is this important? Because gas stations that supply ethanol all run different ethanol percentages. It is not safe to run the same boost level on ethanol that has a 70% value when compared to ethanol that has a 40% value. 

This is a complete plug and play system that allows users to run ethanol without compromising the factory fuel compensations. Once installed, you can monitor the ethanol content through the V3 Accessport. And while utilizing the OEM fuel and electronic connectors, the Ethanol Sensor Kit will measure the ethanol content of the fuel being fed to the motor. This data is then converted into a signal that the ECU can use for adjusting calibrations. Included in this kit will be a billet aluminum converter case, OEM quality electrical and fuel line connectors, as well as hardware to make this kit ready for installation. 

Please note that this kit requires custom tuning for proper use. 

FITMENT NOTE: This is for manual transmission models only.


Brand: COBB Tuning
Includes Tune: No
Plug N Play: Yes
Sensor Included: Yes
Type: 3 Pin Flex Fuel Ethanol Sensor Kit
Mfgr. Warranty: 1 Year
Condition: New Product
Return Policy:

RallySport Guarantee - 30 Days

Items that are covered under the RallySport Guarantee offer a 30 day no questions asked return policy.

RallySport Guarantee items may be returned within 30 days of the original invoice date and must include all the original parts and contents for a refund.

The RallySport Guarantee does not apply to products that have been modified, damaged, misused or abused. All returns require an RMA (Return Merchandise Authorization) Number, and freight charges are strictly non-refundable. For more information regarding our freight refund policy, please refer to our return policy page found HERE.
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  • Q: Cobb flex fuel kit.  04STI2 years ago

    Is there anything else I need to buy with this flex fuel kit? Besides fuel injector, fuel pump and tune? Is it a complete plug in and play kit???
    • 0 of 0 people found the following answer helpful

      A:  This is the complete kit. An upgraded Fuel Pressure Regulator would be suggested.

      Michael N.
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  • Q: Fuel pump / injectors  502sti3 years ago

    Will this run on stock fuel pump and injectors? If not what would you recommend? Future power goals are in the low 500s if that helps.
    • 1 of 1 people found the following answer helpful

      A:  You'll want to upgrade the injectors and fuel pump before you install this. Running ethanol will max out stock injectors very, very easily. If you're going over 500whp with ethanol, you'll want to run 1700cc injectors at a minimum. For the fuel pump, consult your tuner, but you may need explore options like running multiple pumps or a surge tank.

      Marcus E. @ RallySport Direct 3 years ago  
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  • Q: after tune  Steve3 years ago

    if i got a tune on e85 and then got this kit in the future (after tune), would i need to retune it or would it just adjust my custom map parameters accordingly on its own?
    • 0 of 0 people found the following answer helpful

      A:  Your tuner could probably just tweek the current map that you would have for the E-85 but that would be something you would need to discuss with him. You WILL need a retune after installation of this kit.

      Tyler A. @ RallySport Direct 3 years ago  
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  • Q: True FlexFuel?  BananaSammiches3 years ago

    Just to clarify, once and installed and properly tuned, will this enable me to run my car as a true FlexFuel vehicle? That is to say, will I be able to switch back and forth between gasoline and ethanol without changing maps?
    • 1 of 2 people found the following answer helpful

      A:  No. You will need to change maps if you are going to be running just gasoline, pure ethanol and if you are running a mix. Each will require a different map that you will need to switch to.

      Tyler A. @ RallySport Direct 3 years ago  
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