SKU ER1-K1-0050 • 0.4166 lb / 189 gm
ISBN 1-895882-32-X • 8.5 x 11

Important Notes: 
Regardless of what you read elsewhere, we have discovered that the EFIE works on ALL types of oxygen sensors, including Titania (varying resistance) sensors, A/F sensors and wideband sensors.

We do not make an EFIE that controls more than one oxygen sensor. Since nearly every component on the circuit would need to be duplicated anyway, it makes no sense (to us) to stock two different versions of the same circuit. One EFIE per oxygen sensor also allows the customer flexibility during installation.



Build it Yourself! Easy to add upgrades as per the EFIE Manual (sold separately). 

This circuit board and components are identical to our fully assembled EFIE Device.

The EFIE Kit Assembly, Installation and Operation instructions do not come with the kit.  They are available as a download from the EFIE Resources.

You do get automatic access privileges to the EFIE resources by buying an EFIE Device or this Kit.  You log into the EFIE Resources through your account.

The EFIE connects directly to your oxygen sensor and is compatible with ALL oxygen sensors. You need one on each oxygen sensor mounted before the Catalytic Converter.

The EFIE allows you to retain all your power and performance while taking advantage of increased mileage. No matter what fuel saver device or method you use on your fuel injected vehicle, you’ll need the EFIE to unleash the full potential of the fuel saver.

The EFIE alone can save 5% – 10% on your fuel bill, simply by ‘leaning’ your fuel mixture. We do not consider it as a fuel saver on it’s own. It is designed as an ASSIST for fuel savers.

Actual mileage gains depend on the capability of the fuel saver(s) you apply to your vehicle.

Additional information

Weight 6.6656 oz
Dimensions 4 × 1.5 × 1.5 in


There are no reviews yet.

Be the first to review “EFIE (DEVICE) KIT”

EFIE Resources

EFIE Kit Assembly
EFIE Bypass Notes
Nowling Version EFIE
Version E Kit Assembly Notes
EFIE Inside Story
EFIE Parts, Tools & Supplies
Q ~ Will the EFIE damage my computer?
Q ~ What about the Volo?
Q ~ Digital vs Analogue EFIE
Why does Vapor Fuel increase exhaust oxygen?
Will Your Fuel Saver Work for me?
What Fuel Savers do you recommend?
Will installing a fuel saver affect my vehicle Warranty?
Does lean burning cause engine damage?
Do your fuel savers cause engine damage?
Why people DON’T buy Fuel-Saving Technology
What is CEIT?
Do I need an EFIE?
1. What Fuel Savers are recommended for my vehicle?
Do I install on the O2 sensor behind the Catalytic Converter?
Do I need a MAP Enhancer?