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  1. #1

    Default FICHT Injectors Gen 1

    1999 Evenrude 115HP FICHT E115FPLEEN. Fuel injector questions.

    1st question. How is the FICHT injector coefficient calculated?
    Is it calculated with how much fuel is dispensed with a single stroke, over a period of time? I DUNO. How is it metered to get the coefficient. Thru flow delivery or atomization? I DUNO again.

    2nd question what exactly is the coefficient? And how does the EMM calculate fuel distribution based on the said Coefficient? Yeah thats a lot for 2 questions. I just dont have the data to answer the questions 1 or 2.
    Abq Max

  2. #2
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    Default Re: FICHT Injectors Gen 1

    As I understand it in a simple way.-----The emm calculates a signal to be sent to the injector.-------But the emm does not know how a particular injector responds to a given signal.------4 injectors may not all behave the same way.-------Therefor the emm must be matched ( correction factor ) to each injector to deliver the correct amount of fuel.
    Last edited by racerone; 02-28-2020 at 06:59 AM.

  3. #3
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    Default Re: FICHT Injectors Gen 1

    Here is what racer stated in tech terms.....

    State-of-the-art fuel injectors can be defined by a third-order polynomial to define their performance curve and to optimize performance of the fuel injected engine. Such systems are preprogrammed to use a set of fixed coefficients when replacing fuel injectors. Therefore, these replacement fuel injectors must be manufactured with very precise tolerances so as to operate efficiently with these fixed coefficients. The present invention includes a method and apparatus that allows the use of production fuel injectors that are more economical since they can be manufactured with wider tolerances. The production fuel injectors are supplied with a computer program and a data file having a set of replacement coefficients that are determined especially for that particular fuel injector. The approach allows the restoration of the existing coefficients if the replacement fuel injector does not solve the service problem experienced by the user of the fuel injected engine. The new, replacement fuel injector, together with its specific coefficients, can then be used in another application.

    METHOD AND SYSTEM FOR FUEL INJECTOR COEFFICIENT INSTALLATION

    BACKGROUND OF THE INVENTION

    The present invention relates generally to fuel injection systems for internal combustion engines, and more particularly to, a method and apparatus for installing fuel injector coefficient data, that is specific to a particular fuel injector, in an engine controller when replacing a fuel injector.

    In typical prior art fuel injected engines, it is generally considered desirable that each injector deliver approximately the same quantity of fuel in approximately the same timed relationship to the engine for proper operation. It is well known that problems arise when the performance, or more particularly the timing, and the quantity of fuel delivered by the injectors diverge beyond acceptable limits. For example, injector performance deviation or variability will cause different torques to be generated between cylinders due to unequal fuel amounts being injected, or from the relative timing of such fuel injection. Further, knowledge that such variations occur, requires engine system designers to account for this variability by designing an engine system to provide an output equal to the maximum theoretical output less an amount due to the worse case fuel injector variability rather than design a system for peak or maximum cylinder pressures or output.

    Various attempts have been made for solving these problems associated with fuel injectors. One straight forward approach is to simply adhere to rigid manufacturing and test procedures to assure each injector meets a rigid desired design specification. Unfortunately, the increased manufacturing and assembly costs and the low yield of acceptable units makes this approach undesirable.

    Sophisticated electronic equipment and control have made it possible to better control the problem of timing and delivery variations of similar fuel injectors. One such control involves compensating for individual injector variations and includes an electronic control module having a memory for storing compensation signals for each injector. The compensation signals used are derived from observed performance parameter values taken at a number of operating conditions and further include a plurality of sensors for detecting at least one and preferably a number of operating parameters. One or more operating parameter signals are then generated which are then provided to the memory. The electronic control module adjusts the base fuel delivery signal for each injector as a function of the compensation data signal for that injector. Unfortunately, some of the more complex and advanced fuel injectors now being manufac- tured do not follow readily predictable fuel-flow characteristics with increased pulse-width inputs, as was the case with earlier style injectors. Consequently, unless individual compensation signals are determined for an extremely large number of operating points resulting from different pulse widths, such systems would not operate satisfactorily with those advanced fuel injectors. Also, the amount of memory to store a sufficiently large number of compensation signals covering the full range of fuel injector operation would be excessively large, and the cost involved in the necessary testing to determine such a large number of compensation signals would be unacceptable.

    The advanced fuel injector are very complicated and difficult to manufacture and therefore it is very difficult to have consistent operating characteristics between injectors even though they are intended to be substantially identical. Further, although varying pulse width of a control signal is used to vary the amount of fuel an injector provides to a cylinder (hereinafter referred to as fuel flow or flow rate), a performance curve of these complicated fuel injectors (fuel flow vs. pulse width) cannot be accurately defined by a second-order polynomial as can some older types of fuel injectors. Instead, the advanced fuel injectors must be defined by a third-order polynomial. Consequently, determining the pulse width for a desired RPM by extrapolating between sample data points does not provide satisfactory performance. By calculating the pulse width for each fuel injector individually for each desired RPM setting, substantially increased effectiveness of these advanced complicated fuel injectors can be achieved.

    To determine the proper pulse width for a desired RPM for each fuel injector used in the engine, the coefficients for a third-order polynomial, which most closely define a performance curve of each fuel injector, are stored in a read/ write memory associated with a specific cylinder in the engine. In addition, the basic form of a third-order polyno- mial is also stored and available for use by a microprocessor in the ECU (electronic control unit). The microprocessor retrieves the coefficients for each fuel injector and then uses the coefficients for the specific fuel injector to solve the basic third-order polynomial to determine the appropriate pulse 25 width for a given throttle position or desired RPM thereby causing the correct amount of fuel to be injected into the cylinder to achieve the desired RPM.

    Before the coefficients of a third-order polynomial representing the performance curve of a specific fuel injector can be stored in the read/write memory so as to be retrievable by the engine ECU, they must be determined. It is also important that a failed fuel injector can be replaced by a new injector which will also operate effectively with any cylinder.

    Accordingly, each fuel injector is tested on a test flow bench by applying a signal pulse having a selected minimum width and then measuring the fuel flow rate. The pulse width is then increased a known amount and the resulting fuel flow rate again is measured. The process is repeated a number of times, such as 8 to 10 times, to obtain a series of data points which relate pulse width to a fuel flow rate.

    When an engine is initially manufactured, the coefficient data can be determined empirically by any such method. Coefficient data for each of the particular fuel injectors to be installed in the engine is written into read/write memory for use by the ECU microprocessor. To subsequently replace a failed fuel injector, it is then necessary to replace the third-order polynomial coefficient data to the read/write memory over the coefficient data of the failed fuel injector, so that during future operations of the engine, the new coefficient data will be available for use by the ECU microprocessor. To simplify this service process, the prior art preprograms a set of service injector coefficient data in the ECU memory and manufactures all service injectors under stringent tolerance requirements so as to function with the known service coefficients. In this manner, whenever a fuel injector fails, one of the special service fuel injectors is installed, and the ECU is simply instructed to use the service coefficient data for that particular cylinder. While this approach results in satisfactory operating conditions, it is relatively costly. That is, to manufacture each service injector with such stringent tolerances so that the flow rate satisfies a desired performance curve dictated by the fixed service injector coefficient data, results in a relatively expensive replacement fuel injector.

    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  4. #4
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    Default Re: FICHT Injectors Gen 1

    ABQ------Do you know what the time frame is for these injectors to operate.----You could calculate this with an engine running at 5500 RPM.-----Let us know the amount of time available in which an injector must operate.

  5. #5
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    Default Re: FICHT Injectors Gen 1

    The 1999 was a ECU motor..and you would need to figure in the imputs from the
    TP, WT, WT, AT senors to get calculations.
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  6. #6

    Thumbs down Re: FICHT Injectors Gen 1

    Quote Originally Posted by racerone View Post
    ABQ------Do you know what the time frame is for these injectors to operate.----You could calculate this with an engine running at 5500 RPM.-----Let us know the amount of time available in which an injector must operate.
    Ok now is a good time to give you the 2 month history

    Long post. for two questions. All of my first two months history with this rig. In December, for a few dollars, won a very clean, Very Good Condition. Garage kept 1999 OMC 17' Ski and Fish Javelin suited with a 1999 Evinrude 115HP FICHT. E115FPLEEN. The rig is in almost new condition. Well kept. I won the boat at auction so I was only able to gather very little from the owner. I've read the bad about the Evinrude FICHT 1st GEN motors but a lot of the majior problems were not with the 115hp and lower HP power heads. The tank was bone dry and clean. One can of sea foam to start, 25 gallons of REG chevron gas (88 octane @ 5000ft elevation).
    First attempt at the lake, engine failed to start.
    Back at home, I read forms....I Purchased a fuel injection test kit. Spark plugs, Fuel filter. I hook up the pressure gage and 0 psi was the result with key in run position. I checked, It is sending 12Volts to the fuel pump. I pulled the Carter fuel pump with the vapor canister and disassembled it. Yes the thing everyone says is not fixable. I cleaned it up. I managed to get the frozen fuel pump to free up and run. I reassembled the contraption and hook it back up. Now I have 25 psi fuel pressure. Ok...I read more forms.... Change the Fuel filter, Gap new Plugs. Index new plugs. Hose and muffs in place water on, I hook up the computer. It starts!
    It ran at high Idol 1600 rpms for 6 min I bump the throttle it now runs at 650-655 RPMs. The PC connection using the Evinrude software acquired from ebay, shows no faults. OK it say Run Hours are 79. and something. The software tells me the break in period has been accomplished. Nothing Else.
    Back at the lake, Hard to start but after 15 min got it running. Idled it at 650 rmps the dock for 15 min. head out to open water shift into gear, DEAD! re start shift into gear with a lots of throttle feathering and simultaneously choking. got it to plow water at 2500 RPM at WOT. I go for about 15 min to the far side of the lake. i let the engine run, for an hour while I fish the cold winter waters. After 1 hour I shut it off and continue to fish for a couple more hours. I start up the engine after 2 hours it fires and runs with one crank! All right! I shift into gear, the engine engages and runs. I head back across the lake, this time with a lot less throttle feathering. I make 2800 rpms and was able to get on plane. On plane I make 4200RMP's. Wind is in my face the lake is to rough to continue at this speed. I seek shelter on the west shore and continue to troll with my main motor at 2.2 MPH. I drop off the Wife and boy at the dock. I secure everything loose in the boat and go back out to open water. Without feathering now just a sluggish throttle control, I get to 2800 rpm and minipulate trim to get on plane, there i was able to WOT GPS says making 37.2 MPH, WOT only making 5200 RPMs. Ran out of day time I spin it around and trailer my boat.
    I'm thinking the injectors are still dirty. Getting better as the engine runs with clean gas and SeaFoam to Help de-carbonize the power head. I'm going to purchase an old head, so I can mount one injector at a time. I'll flood and fire the injector with 30 psi air behind 100% B-12 injector cleaner. let it set for 15 min come back and fire it 10 more times. Flood the injector body and let rest, repeat until the injector shoots clean. (this type of injector is not like the automotive type, it comes apart when not installed on the power head) I've always worked on my own stuff.

    Any one got any new magic i have'nt tried. I'm just still green to this motor and its design.
    Last edited by ABQ_Hatrick; 02-29-2020 at 01:22 AM.
    Abq Max

  7. #7

    Default Re: FICHT Injectors Gen 1

    What da.....
    Abq Max

  8. #8

    Default Re: FICHT Injectors Gen 1

    OK guys, I've owned boats since 1988, Johnsons Merc's, mainly all carbureted. So i'm in a steep learning curve with this 1st Gen FICHT DFI injection.
    Fazbullet the only response i have for you is whats with Dr. report you left. That was the most ambiguous read I have read in the last 10 years! Not understanding your need for big wordz. ahhh thanks I think. Im guessing the boyz at FICHT in 1999 before bankruptcy were drinking some pretty strong Kool-Aid.

    Ok, read the big post it gives you the 2 going on 3 month history....

    im seeing progress but it seems like the only real information on the 98, 99 115 FICHT is FORMS.

    the reason for my questions is I want to challenge the coefficient that is plugged into my EMM. I'd like to measure for my self and say Yep thats right. but all I have currently is an EMM that says the coefficient is this. What is the litheness to challenge the coefficient a bankrupt company has left in my EMM. To know weather its right or wrong.
    If you read the long post you now know I've only been able to achieve 5200 RPM's, racerone, still not fast enough to test... this engine is clean, solid 120PSi all cylinders and the hold after a 5 min leak down test. Fuel now flows at 22 psi while running. Up from ZERO when I first purchased it. New plugs indexd and torqued. My instinct is leaning me toward dirty injectors. I'm currently building a bench top FICHT injector cleaning station, that should do the trick. I believe Im dealing with varnish in the fuel sustem/ injectors, neglected from years gone by setting idol. The EMM reports 79 hours run time. That just short of eight, 8 hour days of run time. It practically new. The last hour i ran it got up to 37MPH max fast so far.
    im floundering for an answers. Im a gear head and the work just passes time for me. I have not found a specific manual for the 1999 Evinrude 115hp FICHT. looking for a manual more geared to the FICHT side of this engine.
    Abq Max

  9. #9

    Default Re: FICHT Injectors Gen 1

    faztbullet, TP=Throttle position, WT= inlet water temp?, WT= outlet water temp? AT = Barometric pressure? None of my carburetor Power heads had an EMM, ECU, ECM or any thing computerish connected.
    Abq Max

  10. #10

    Default Re: FICHT Injectors Gen 1

    Quote Originally Posted by racerone View Post
    ABQ------Do you know what the time frame is for these injectors to operate.----You could calculate this with an engine running at 5500 RPM.-----Let us know the amount of time available in which an injector must operate.
    Racerone I dont even know if im asking the right Question! 5500 RPMs lol not yet!
    Abq Max

  11. #11

    Default Re: FICHT Injectors Gen 1

    I see why others would run from the 1 Gen FICHT systems. They require very expensive diagnostic equipment. I do not have access to.

    Q: 1st question. How is the FICHT injector coefficient calculated?
    A: By a Fuel spe******t that has access to A FICHT injector flow analytics system.

    Q:
    2nd question what exactly is the coefficient? And how does the EMM calculate fuel distribution based on the said Coefficient?
    A:
    coefficient, which most closely defines a performance curve of each fuel injector, are stored in a read/ write memory associated with a specific cylinder in the engine. The coefficient is unique to each Injector .This coefficient stored in the EMM (EVINRUDE/FICHT TERMINOLOGY). The coefficients for each fuel injector are unique to the specific fuel injector to COMPENSATE FOR manufacturing imperfections, it solves the pulse width for a given throttle position or desired RPM thereby causing the correct amount of fuel to be injected into the cylinder to achieve the desired RPM.

    This is why we send them off to be professionally rebuilt.

    OK so I'm stuck with cleaning them as best I can.
    Abq Max

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