The Electronic Fuel InjectionEnhancer (EFIE, pronouncedEe-Fy) (t) is not a fuel saver, in andof itself. Yet, it is likely the greatestenhancement to be invented for fuelsavers in recent history. The EFIEallows fuel savers like hydrogen to work on FuelInjected engines.Most modern fuel systems use anoxygen sensor to tell th computer the air: fuelratio of the engine.Believe it or not, the design of oxygenSensor feedback actually preventsEfficient combustion!Increasing the combustion efficiencyOf an engine increases the exhaustOxygen percentage because:The engine uses less fuel for theSame volume of air;More oxygen is free because theEngine produces less carbonMonoxide and;Less oxides of nitrogen form.The increased oxygen content in theExhaust is 'read' by the computer toBe a (Lean mixture in the engine.The computer then adds extra fuel toBring the fuel injection back to 'normal'.Solving this problem requires the EFIEdevice, this electronic circuit that can beCompletely built with parts from aNeighborhood electronic parts store or internet electronics parts store,.

The EFIE allows you to add a'Floating (Voltage offset', in seriesWith the oxygen sensor, so the fuelComputer thinks the mixture is richerThan it really is. That way, you canCompensate for increased exhaustOxygen caused by increasedCombustion efficiency.Applying the EFIE, is like adding aLittle battery in-series with the oxygenSensor. This 'battery' is powered byThe vehicle. Therefore, it will neverFade or go dead. It is completelyAdjustable to a few millivolts forOptimal custom tuning.The result: your vehicle's computer isEntirely unaware that the oxygenContent of the exhaust has increased.The EFIE is designed to work with any o2 sensor with 4 wires or less, not the 5 wire typeThe EFIE will not void any vehiclewarrantee.It is against federal law for anyvehicle manufacturer to void thewarrantee simply because thecustomer installed any kind of aftermarketdevice.Further, if the vehicle has problemsand the vehicle manufacturer (orrepresentative) wants to blame theafter-market device, the onus is onthe vehicle manufacturer to prove thatthe after-market device caused the

problem in the first placeOf course, the vehicle manufacturer'swarrantee does not cover the aftermarketdevice or the EFIEControl the Computer By Knowing How It Thinks,The computer is designed by thefactory to assume that a certainreadout of the oxygen sensor (.5 voltor 500 millivolts) means the enginehas a correct air: fuel mixture. Thefactory setting is correct, as long asthe engine is totally OEM.Oxygen sensors generate a voltagesignal due to the difference of oxygenon the inside and outside of theexhaust pipe. We've seen oxygensensors go up to 1.9VDC and as lowas -2VDC. They are calibrated tosuppose that O.5VDC is equal to the14.7:l air: fuel ratio.The oxygen sensor does not tell thecomputer the actual air: fuel ratio.The computer infers the air: fuel ratio

based on it's set internal parametersand the oxygen sensor reading.Burning the fuel more efficiently,causes the oxygen content in theexhaust to rise an average of 2%.This is the oxygen that didn't formcarbon monoxide and oxides ofnitrogen. The carbon dioxide goesup a bit and the hydrocarbons drop

off by at least half.The electronic feedback fuel injectioncomputer can't imagine that a higheroxygen content is possible withcomplete combustion. It figures thefuel mixture is lean and signals theinjectors to richen the mixture in orderto bring the oxygen content backin rangeOxygen sensors are very accurate ina very limited range. They must alsobe heated to at least 600" F to readaccurately. Temperatures under700" F will cause the sensor tocarbon up quickly.Exhaust temperatures, at idle, tend tobe lower than 600" F, so oxygensensor readouts can't be trusted. Youmay have to shut down your hydrogendevice at idle. Alternatively, you canbuy a heated (three wire) oxygensensor. We've had extremely goodresults with heated oxygen sensors.The 14.7:l air: fuel ratio that isconsidered ideal is really a pollutioncompromise. Don't be fooled, it is notthe most efficient burn ratio. It justhovers on flooding to prevent themixture from heating up. Heat is veryimportant here, because it is heat thatcreates the Oxides of Nitrogen(iNOx). Oxides of Nitrogen arecreated anytime you heat air over

2100" F. So if you control the heat,you reduce the oxides of nitrogen.14.7:l is the best pollutioncompromise using liquid fueltechnology.Fig. 2

However, when you add a fuel saver,the combustion characteristics arechanged, so you have to adjust theoxygen sensor output signal.Vapor technology and water injectionare superior options for reducingheat.Water injection will help preventcarbon buildup in your engine andpromote better combustion. But,because it also adds extra oxygen inthe exhaust, water injection will foolan oxygen sensor into thinking thatthe fuel ratio is leaner than it actuallyis. You need to install an EFlE tocorrect for the extra oxygen when you

add water injection.The chart shows the typicalreasoning for the 14.7:l air1liquid:fuelratio. When burning vapors, muchleaner mixtures can be burned, withreduced NOx production for tworeasons:1. The burn time is much shorter,which limits the time that NOx has toform.2. You can reduce the flametemperature by reducing the amountof fuel. If the combustion has barelyenough fuel to burn, it will be cool.Another way to reduce temperature isto add water injection. Conventionaltechnology shows that fuel will easilyburn in air: fuel ratios as lean as 26:l.

The EFIE's function is to correct theoxygen sensor's output to match thecorresponding increase in efficiencycaused by the combustionimprovement. With the EFIE, thecomputer won'tfisht the fuel saver byadding extra fuel.Applying the EFIE by itself is notrecommended. The EFIE shouldalways be applied in addition to acombustion enhancement device ormethod.Use of the EFIE without combustionenhancement could result it an

1 overly lean mixture, increasingpollution and decreasing the life ofthe engine.GETTING PARTS >All of the parts in the EFIE deviceare available in most electronicoutlets. They will also carry thenecessary circuit boards, box, wireconnectors, chip sockets, solder, wire,etc. To acquire the parts, simply takethe schematic (Fig. 3) into yourRadio Shack, for example, andpurchase the components.The only component not readilyavailable at Radio Shack (inparticular) is the 200K (Twenty-turncircuit-board-mounted trimmerpotentiometer. These are availablefrom nearly any electronics supplier(see Re.sourrr.s), usually for under$5.00. Radio Shack does sell twenty turnboard mounted trimmers, butonly to about 15K. You could set upa series of trimmers, to do the job.Knowledgeable peoplemay wish to purchase 'componentpacks' of assorted transformers,capacitors and resistors. The range ofvalues in these packs allows forexperimentation of the circuit forYour vehicle's needs. BEFORE YOU BUILD -'IPurchase an experimenter's board to

pre-assemble and test your circuitbefore you Hard wire thecomponents onto a circuit board. It isnearly impossible for your individualcircuit to work correctly withoutsome tuning. There are too manytiny variables in the circuitcomponents. The modest expense ofan experimenter's board saves hoursof hassle and mess that de-solderingand re-soldering causes. Tune thecircuit, then hard wire it to a circuitboard.After you've tuned your circuit on theexperimenter's board, take extraspecial care in assembling it ontoyour circuit board. Remember, allthe components have to fit into yourcircuit box. A neatly done circuit ismore likely to work well.Fasten the circuit into it's box usinga hot glue gun. This allows forgreater freedom of action duringassembly and assures that theelectronics will be secure.

BUILDING THE EFIE Always tie a knot in the outputwires, on the inside of the circuit box,to prevent any stress on the wireswhich could detach the wires fromthe circuit board.Use a chip socket when soldering a

circuit together. This assures that thechip doesn't overheat and makes forquick replacement of faulty chips.The challenges involved in buildingan O2 sensor-corrector (EFIE) aretricky ones. You need to be able tovary voltage in such a way that youcan ad-just it by millivolts. Yet, youhave to work within the capabilitiesof the vehicle electrical system andthe characteristics of O2 sensors.Further, the device must not be ableto harm any vehicle computer.In particular, tuning your transformer(T1 - Fig. 3) is the most criticaldesign parameter.In all three transformer options, theactual circuit remains identical. Totune the transformer you will varyonly C1, R4, and R5. Therefore, youcan assume that all the othercomponents are as described and arewired as per the circuit diagram

Choose one of the followingtransformer options.Option 1: Manufactured TransformerConsider buying a transformer fromRhombus Industries Inc.

We used a T50110 Cfor TI). This is acircuit-board-mounted, generalpurpose, low cost 1:I transformer.

We tuned this transformer withCI=8.7 dnF; R4 = 7.9 K ohm;R5 = 100 Kohm.Option 2: Build Your Own T1Simply wind two 30-gauge varnish coatedmagnet wires together andonto a plastic sewing bobbin, to makeyour own 1 : 1 transformer. Be sure tobum and scrape the insulation off thewire ends before soldering them.Varnish-coated magnet wire can bebought new or salvaged from asolenoid coil.We stretched out two 30 foot lengthson the floor and wound them togetheron the plastic sewing bobbin. Thiscoil came to 3.6 Ohm and .46 (LmHfor both primary and secondary.Vary values of CI , R4 and R5 'ti1 youget 500 dmV across BR.We tuned Option 2 transformer withCI= 0.61 nF; R4 = 107 K ohm;R5 = 382 K ohm.Option 3: Tuning Any TransformerWe tuned Option 3 transformer withCI= 0.61 nF; R4 = 118 K ohm;R5 = 1 K ohm.Chances are you won't be able toobtain the exact transformer used inOption 3. Your coil can be nearlyanything. Adjust the circuitcapacitors and resistances to get theresult you desire. The Option 3

example TI is a very small I: Itransformer (from a salvage catalog)with 40 ohms resistance and.3 1 Henrys inductive reactance on theprimary and 34.7 ohms resistance and.33 Henrys inductive reactance on thesecondary.When you are connecting yourtransformer, it does matter whichsecondary wires are used to run yourbridge rectifier. Change thesecondary leads around, on your testboard, to get the highest voltageacross C3.We used a 'floating' capacitor (C3) toadd 1-olmge in series with theo2 sensor signal.As you increase the resistance of R6,the voltage across C3 rises (bymillivolts and the C3 voltage isadded to the voltage of the o2 sensor,as read by the computer.This is a true 'voltage ofset'and willremain exact regardless of the oxygensensor voltage. Exnnzple EFlE offsetat 200 milli~~olwtsil l cause an o.rygensensor readout of 500 millivolts toread 700 millivolts to the computeruncl an oxygen sensor readout of100 r millivolts to read 300 r millivoltsto the computer.

Variable Design Components:

(depending on transformer option)C1, R4, R5Option 1C1 = 8.7 nFR4 = 7.9 K ohmR5 = 100 K ohmOption 2C1 = 0.61 nFR4 = 107 KohmR5 = 382 K ohmOption 3C1 = 0.61 nFR4 = 118 K ohmR5=1 KohmFixed Design Components:(all transformer options)BR = 1 amp @ 200 voltsC2 = 8.8 nFC3 = 200 - 500 ~ u@F 35 VDCC4 = 0.047 UF to 20 UFDl = 1 amp @ 200 volt diodeR2 = 15 KohmR3 = 1 K ohmR6 = 20 turn 200 K pot.R7 = 500 ohm resistor

We use simple inexpensive circuitboard-mounted potentiometers forR6. These require a smallscrewdriver for adjustment. Onceset, you won't have people spinningthe knob. Going past the twentyturns on this potentiometer (pot.) will

simply cause the adjustment screw toslip. As far as we are aware, nodamage will be caused.Connect the leads to R6 in such away that when the pot. is turned allthe way to the left (counterclockwise),the pot. is 0 ohmsbetween the center pin and the pinthat you connect to R5. Circuitand be sure the circuit is grounded (towire 1).Frequency control is very importantto tune TI. You may need a higher orlower frequency to tune your 555 toyour transformer. You will knowwhen your 555 is best tuned to yourtransformer by monitoring secondaryoutput of the TI with a volt-meter.The highest voltage indicates the besttuned. Be careful not to push thehigh frequency limits of your 555.Some of them don't like to go above500 KHz. Sizing C1 upward (more capacitance) . Increasing the resistance of R2decreases the frequency of the 555.

The R4 controls both the amperage output of the 555 and how much that. amperage affects TI. By having a

voltage drop across R4, there is lessvoltage to apply to T 1 and theinductive reactance is less. R4 limitsthe current from the 555 to a valuethat allows the 555 to activate T 1without any other electroniccomponents. You'll need to adjustR4 to get optimum performance.Try to keep the value of R4 high, tominimize current flow. This keepsthe 555 chip cool. If your TI has ahigh resistance and/or inductivereactance, you may not need as higha value for R4.

Adjust R4 by experimenting withvarious sized resistors or by installinga variable resistor, 'ti1 you get thehighest readout (millivolts) across theC3. If the millivolts is too low(< 350 millivolts), then size R4 toless resistance. If the millivolts is toohigh (> 500 millivolts), then size R4for more resistance. Once you'veadjusted R4 for adequate voltageacross C3, your internal circuit boardadjustments are finished. Use a fixedresistor.for R4 in the finished EFIE.Unless you have a faulty oxygensensor, you should not require morethan 500 millivolts output of theEFIE. This is the limit of the oxygensensor's input to the fuel computer.The fuel computer can't adjust anymore - .Marking R (rich) andL (lean) indications on theEFIE box are handy foradjustment of R6. The indicationsshould show the direction to adjustR6 so that the EFIE voltage lowers(richer mixture) and rises (leanermixture) respectively. We useclockwise toward lean.S 1 (Switch I , (LDPDT), Green andRed (LLED diodes and R7 (500 ohmresistor) are optional. R7 is needed ifusing either LED; R7 is not needed if

you choose not to have any LEDs.S 1 allows you to shut off the EFIE,without losing your R6 adjustmentsetting

Wire Color Code#I = Black,#2 = Green,#3 = White,#4 = Red.The 7812 voltage regulator, in aTO-220 AB case, is included to keepthe voltage to the 555 chip steady.Vehicle operating voltage usuallyfluctuates a bit. If the voltagefluctuates to the 555, the voltage onC3 will change. You want C3 tohave a steady (within 5 millivolts ofthe set-point) voltage.The 8 pin 555 timer chip is set up asa high frequency (Lastablemultivibrator with a 50% duty cycle.The high frequency allows verystable voltage control to C3, byapplying the voltage in very quickpulses to the primary coil of TI.

( INSTALLING THE EFIE )The EFIE is spliced into the wireleading from the oxygen sensor to thevehicle :s computer. This allows theEFIE to modify the voltage signalcoming from the oxygen sensor,

before the signal reaches thecomputer

Step #1Connect the Black (wire #1) from theEFIE to vehicle ground (negative).Make sure to ground the EFIE to thevehicle very well.

Step #2Use an ignition-switched powersource for the positive input to theEFIE (Wire #4, Red), so that theEFIE will shut off when you shut offthe key. The fuse box normally hasspare terminals for this sort of thing.Or you can tap into power relaypower wire that shiits off when thekey shuts off, such as the radio power

Step 3Connect wire number 3 (white) from EfieTo the wire leading to the vehicles computer.

Step #4Connect Wire #2 (Green) from theEFIE to the wire leading from theoxygen sensor.Wires #2 and #3 are routed to theoxygen sensor output wire, down nearthe oxygen sensor itself. There isusually a plug connector in the wirenear the oxygen sensor. If the

oxygen sensor has just one wire, youcan splice the EFIE wires into theplug connector. If the oxygen sensorhas more that one wire, cut theappropriate wire on the vehicle sideof the connector. The wires comingfrom the oxygen sensor are specialhigh - temperature wires that aredifficult to solder. Assure yourself ofa water-tight connection. Keep wiresaway from the exhaust pipe's heat.Some oqgen sensors have more thanone wire. Extra wires could beexhaust ground or oxygen sensorheating wires. Your vehicledealership should he able to tell YOUwhich wire is the correct one. Youcan always tell the oxygen sensoroutput wire because it will have noelectrical continuity to the vehicles,Ground, power (positive) or theexhaust pipe. In other words, testingwith an ohm-meter will show infiniteresistance when connected betweenthe oxygen sensor outpiit and themetal body of the oxygen sensor andany other wire on the oqgen sensor

Installation lipsInstall the EFIE box under the dashin an assessable place. That way youcan flip the switch and fine tune theadjustments as you drive. Dash

mounting (or under dash) allows theEFIE electronics to be warm and dry.If mounting the EFIE under the hood,make sure to weather-proof it well.Connect the EFIE wires to the carwith a plug connector so that the unitcan then be easily removed for repairor reinstallation in another vehicle.Attach the EFIE box to your chosensurface with Velcro. Attach theVelcro with contact cement or glue.Alternatively, you can attach theEFIE to your vehicle with wire ties.Don't use crimp connections. Solderthe connectors to the wires to preventloose or corroded connections. Sealwith shrink-wrap or silicone.More than one O2 sensor: adjust themall to the same voltage at first - thenexperiment with changing individualvoltages.Vehicles with more than one oxygensensor need an EFIE on each oxygensensor.

Operating Characteristics of theEFlE CircuitDue to the large capacitanceinstalled in the EFIE (C3). it takesfive to ten minutes for the unit tostabilize at any new setting. Thisoccurs every time the EFIE is turnedon or adjusted.

The EFTE capacitor (C3) quicklydrains while the EFIE is turned offand will require a few minutes tocome back to full voltage when theEFIE is turned back on. This softstart feature allows the vehicle'scomputer to adjust slowly to theincreasing voltage signal.TI secondary allows C3 to float. inrelation to the vehicle's ground

reference, because of the isolationeffect of transformers.TI allows C3 to act as anadjustable voltage 'battery' in serieswith the O2 sensor. By adjusting R6,we adjust the discharge rate of C3.This adjusts the voltage because theinput electricity to C3 is fixed. Thevoltage is usually controlled to plusor minus two millivolt (0.002 volt).+ Be sure to apply Dl acrossthe TI primary as shown, orthe coil inductive kickbackwill reach > 100 volts. It could burnout the electronics. This diodewheels the coil's inductive kickbackinto the coil.Zero ohms on R6 will not cause thevoltage of C3 to go to zero becauseof the series resistance of R5.Voltage of C3 is the actual voltageoffset. A fixed amount of energy is

added to C3 by the EFIE circuit.This makes it simple to control theactual voltage of C3 by 'draining' thecurrent through R5 and R6.If you drain the current from C3faster than the current is brought infrom the EFIE, the voltage of C3 willdrop. Decreasing resistance of R6will cause C3 to stabilize at a lowervoltage. R6 and R5 control how fast thecurrent drains. Using a twenty turnpot for R6 allows fine tuning of the EFIE output by accurately controllinghow fast C3 will drain.Because the vehicle's ignitionvoltage is higher when the engine isrunning, all EFIE adjustments shouldbe made while the engine is running.alternatly, you can bench test it with aDC power supply set at 13.5 volts and< 14.5 volts. The alternator voltageis greater than the battery voltage..And due to the voltage drop acrossthe voltage regulator, the EFIE issomewhat voltage sensitive.If the ERE is shut off, by switchingoff S1, then the vehicle's oxygensensor system operates normally.Remember that use of a volt-meterbetween the oxygen sensor input(green wire # 2) and the output to the

computer (white wire #3) will cause avariance in the actual output. Outputwill rise by a few millivolts when thevolt-meter is removed, because thevolt-meter is actual load, taking abit of power to operate.A lower voltage on C3 causes thevehicle's cornputer to richen towardnormal and a higher voltage on C3will cause the velzicle's computer tolean.Remember, you ore not really leaningthe air vapor mixture if you are usingcombustion enhancement devices.Your are simply putting in less fuel toget the same exhaust vapors.If you monitor the o2s sensor voltageand your C3 voltage, you will notethat the cornputer will try to keep thetotal voltage at 500 millivolts (whenthe vehicle is warm and not idling).If you get too high an exhausttemperature or your vehicle Sperformance drops, richen themixture by reducing C3 voltage.Use a volt-meter across wires #2 and#3 to get an idea of what voltageoffset you are applying. Connectingthe volt-meter from wire #2 toground (wire #1) will show actualo2 sensor output. And connectingthe volt-meter from wire #3 toground (wire # I ) will show the

combined voltages of the o2 sensorand the EFIE

Operating the EFIE While DrivingSwitching the EFIE off (redlight), instantly disconnectsthe ignition power from theEFIE circuit and instantly connectsthe oxygen sensor output directly tothe vehicle's fuel control computer.There is no delay time, the computeris instantly getting direct true oxygensensor input. This feature has beenadded in case you want to switch theEFIE off for tweaking or because youwant to test vehicle response onvehicle-computer-tester and pollutionmachines. The EFIE is designed to be fullyautomatic. Once it has been adjustedno further tweaking is needed, unlesssomething changes. Changes includebut are not limited to: engine tune-up,adding-or subtracting combustionenhancement devices, etc.The ONLY thing turned on whenthe EFIE is off is the red light, whichsimply indicates the switch positionat a glance. If neither the green orred light is on, then the ignitionpower to the EFIE has beendisconnected; there is a malfiinctionin the EFTE unit; or you have a

miswire. Switching the EFIE on (greenlight), connects the ignition power tothe EFIE circuit and runs the oxygensensor output through the EFIE forvoltage enhancement. For adjustment of R6 (voltageoffset), start with R6 in the richposition, which is the lowest voltageoffset. Warm up the engine anddrive. Slowly adjust R6 to get yourbest economy with the least pollution.Adjustments are best done whiledriving but for safety's sake, use afriend to actually do the adjustmentsor pull over to make each change.Fine tuning adjustment of R6should be carried out over days ofvehicle service. Many vehiclecomputers equipped with O2 sensors'learn' as they go. So you have toallow the computer to get used toyour adjustment before you knowwhat the actual effect has been.We can't tell you what the bestvoltage offset will be in yourapplication. This is success by trialon your part. However, we can giveyou some ball-park figures to workwith: With effective combustionenhancement devices, you should beable to offset at least 300 millivoltsand you'll likely be somewhere

between 450 and 500 millivolts.If your 'check engine' light comeson, then you've applied too muchvoltage offset and the computer can'tadjust the fuel injector output anymore.

It is easy to determine your air: fuel ratio while traveling5 down the road by using anoxygen sensor and a (highimpedance) voltmeter. Put thepositive lead of the voltmeter to theoxygen sensor signal and ground thenegative. Read the millivolts and

Use the EFIE only after some sort ofcombustion enhancement device ormethod has been added to thevehicle.Vehicles with more than one oxygensensor need an EFlE on each oxygensensor.Your actual mileage gains will dependon the capability hydrogen generators that you apply to your vehicle(s).

PARTS LIST

I x #555 8-pin timer chip #276- 17 18I x 8-pin chip socket (for a #555) #276- 19951 x 78 12 voltage regulator in a TO-220 AB

case (Future Electronics)1 x 20-turn (200k ohm) potentiometer1 amp diode. #276- 1 1034 pin connector, #274-8002Box, #270- 180 10 (for EFIE circuit)Bridge Rectifier, #276- 1 16 1 or #276- 1 152- I amp at 200 voltsCI Capacitor, (for C3), 470 mfd @ 35V,#272- 10 18Capacitor Pak, #272-80 1Circuit board,# 276- 159Glue Sticks (glue gun)1 green LED, #276-0221 red LED, #276-04 1Resistor Pakroll of solderSwitch 1 , DPDT, #275-663Wire, #278-50X (circuit assembly)Wire, #278- 1304 (ERE leads)T OptionsThese conzponents are bused on tran.~fornlaroptions.T50110 (Option I , Rhombus Industries)CI Magnet wire, #278- 1345 (for making atransformer - Option 2)Plastic Sewing Bobbin (Option 2)Induction Pak, #273- 160 1 (Option 3)

GLOSSARYWords that are preceded by (L are defined here.02 = oxygenastable = repeats itselfCET = Combustion Enhancement Technology

DPDT = double pole, double throw switchhard wire = solderIC = integrated chiplean (er) (est) = less fuel or too little fuelLED = light emitting diodemH = mill HenrymV = millivoltsnF = nano-faradNOx = Oxides of Nitrogen (NOx). Oxides ofNitrogen are created anytime you heat air(which is a mixture of oxygen and nitrogen)over 2 100 degrees F.OEM = original equipment manufacturerpin-out = pin numbering system on chiprich (en) (er) = more fuel or too much fuelten turn = 10 full revolutionstwenty turn = 20 full revolutions (greaterrefinement than a ten turn)uF = micro-faradvoltage offset = voltage added to oxygensensor signal

Tools needed

drill (Dremmel preferred)Drill Bits 118" and 1/16"experimenter's board, #276- 175glue gunhemostathigh impedance multimeter #22- 174 -measuring at least 0-20 volts DC and40,000 Ohms - the ability to read capacitance& inductance is a great asset

set of small screwdriversside cuttersoldering ironsoldering iron standwire stripper

Fuel saving is not an exact science.It is an evolving art, requiring time,patience and a commitment tolowering fuel costs.While every effort is made to ensureclean, efficient, cost-effectivemethods and reliable information, Youthe experimenter, must alwaysremember: Countless variables,which we cannot determine, affectany combustion enhancement deviceor method.To reap optimum results, from anyenhancement, your vehicle musthave been maintained in 'good'working order. It is not onlyunrealistic, but entirely unfair, toexpect a mileage enhancer to makeup for poorly maintained engines.Before applying any combustionenhancement method or device, yourvehicle must receive a standardtune-up, .including:ignition systemfuel systemfilters

fluids and lubricationfan beltsbrakes . alternatorGet it done at least twice a year.Only then can you expect mileagegains. Not reaping a fuel efficiencygain is highly unlikely with a reputablefuel saving device or method,