EFIE Installation Instructions
September 30, 2008 – 3:47 pmInstall your fuel efficiency device
The Electronic Fuel Injector Enhancer (EFIE) is not intended to be a fuel saver by itself. You should install a device that is designed to get more energy out of the same fuel, such as a hydrogen gas electrolyzer, a fuel vapor production unit, or other device that gets more power out of the same fuel by increasing the efficiency of the burn.
Locate the oxygen sensor signal wire
The easy way to do this is to look it up in your Haynes, Clymer or Chilton manual for your car. If you don’t have one of these, there is a service at www.ahdol.com where you can pay a nominal fee, and get your wiring diagrams emailed to you. I have also recently found a resource at www.autozone.com whereby you can get your wiring diagram, and specific service manual information on your sensors. However, the information is not available for all cars and trucks. Using the wiring diagram data, you can get the wire color of the signal wire, and hopefully gain access to it up in the engine compartment, where it routes to the computer.
If none of these options are available, you’ll need to locate the oxygen senor and then locate the signal wire by testing. The sensor can have 2, 3 or 4 wires, and you have to know which one is the signal wire. If you have 4 wires they will be:
- Heater 12 Volts +
- Heater ground
- Oxygen sensor signal +
- Oxygen sensor signal ground
If you have 2 or 3 wires, then you can have a common ground, or no heater wires etc. The simplest setup is a single wire, which is the signal wire and the sensor get’s it’s ground from the exhaust pipe. You can use the following procedure to narrow down which wire is which:
- Disconnect the wire harness, turn on the ignition and probe for a wire produces 12 volts. This will be the heater circuit.
- Next find the 2 wires that produce exactly 0 volts. These will be the heater ground and the signal ground. The remaining wire should be your signal wire.
- Reconnect the wiring harness, then strip a little insulation from the signal wire and measure it to ground with the engine running. You’ll get voltage readings constantly fluctuating between 0 and 1 volt, if you have the signal wire. Note, that you have to let the engine warm up a bit before you will get these voltages from the sensor.
- Cut this wire at a convenient location for connecting the EFIE. We’ll call the sensor side of this cut the sensor wire, and the other side of the cut, the computer wire.
Note: rarely an oxygen sensor wiring harness will have more than 4 wires. In this case, the sensor is possibly a “wide band” oxygen sensor. The EFIE has been reported to work with 5-wire wide band sensors.
Once you have determined which is the sensor’s signal wire, you want to get it located up close to the computer. If you used a manual, or wiring diagram, you probably have already located the wire at the computer’s wiring harness. If you had to figure out the wires at the sensor itself, then try to find the same wire at the computer’s wiring harness. It should be the same colors, but test it with an ohm meter to be sure. Sometimes they use the same colors for different things. Even if it’s a pain now, it’s worth it to get the signal wire located up by the computer. This makes cutting into it and hooking up the EFIE much easier.
Locate 12 volt power and ground
You need to ensure that you have switched power, not power directly from the battery. You don’t want the EFIE running 100% of the time. It’s not that the unit couldn’t run 100% of the time, it probably could. But it would slowly drain your battery.
Most of the fuel efficiency devices need switched power as well, and you can often piggy back onto them. Note that the EFIE draws negligible power. You can attach it to any circuit. The best choice for a voltage source is a fuel efficiency device, such as a Hydrogen generator. That way the EFIE only activates when the fuel efficiency device is turned on. Note that when power is shut off to the EFIE, or the EFIE’s switch is turned off, the original connection between the oxygen sensor and the computer is re-established. If connecting to your fuel saver’s power is inconvenient or inappropriate, just use any circuit that is accessory key switched. Your electrical diagram can come in handy here, and if you don’t find another device to attach to, you can usually find a spare circuit in the fuse box (you may have to add a fuse). One installer used the oxygen sensor’s heater power for his EFIE’s power, and this is perfectly acceptable.
Ground can be the vehicle body, engine block or ground from another device, including the ground for the oxygen sensor itself. Just make sure that whatever you choose to use for ground has a negligible resistance (less than 10 ohms) when tested against the negative battery terminal of your car.
Mount the EFIE
You can use the mounting ears to screw down the EFIE to a suitable location on the vehicle body or firewall. Some people like to mount the device inside the passenger compartment of the car.The EFIE is not waterproof. If you mount it under the hood, you will have to take care to cover it if you need to steam or spray clean your engine. If this is something you regularly do, you may want to mount the EFIE in the passenger compartment where it will be protected.
Where to Purchase
There are kits/instructions available from sites that will tell you how to make your own EFIE, but if you don’t have time or the skill to make one there are stores that sell already build EFIEs. If you have purchased an HHO kit or are considering it for a fuel injected vehicle, go to EFIE Devices, to get an already assembled EFIE device.
