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EFI Power Cutting

Discussion in 'Engine and Drivetrain/Mechanical' started by JonnybravoM3, Mar 22, 2018.

  1. JonnybravoM3

    JonnybravoM3 Member

    Hi all

    So I've just gone EFI, FiTech... Today's the first day I properly drive her with the new system.

    My issue is that the car runs fine for a while then it randomly cuts out, power comes and goes, to the extent that it eventually stops while actually driving on the freeway, I'm pushing the throttle and there's no response. I pull over, put the car in park and start it again. Like its struggling to maintain power.

    Could be an obstruction in the fuel lines or could it be that my alternator isn't enough to handle the EFI?

    Anyone experience this before?


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  2. JonnybravoM3

    JonnybravoM3 Member

    I feel it as well during automatic great changes... like the car is hesitating...

    Thing is my EFI system is self learning.. But could it still be a tuning issue?

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  3. Horseplay

    Horseplay I Don't Care. Do you?

    How wa your fuel system set up? What pump are you using? How much fuel
    Pressure does it generate?

    What about your ignition system? Are you using the stock single point distributor or have you upgraded to electronic? The stock unit certainly is t ideal.

    FiTech systems do need to “learn” to be most efficient and deliver best performance so some amount of engine fluctuation isn’t abnormal.
  4. Horseplay

    Horseplay I Don't Care. Do you?

    The alternator or charging system is not to blame.
  5. JonnybravoM3

    JonnybravoM3 Member

    I believe it's the stock ignition, at least i haven't upgraded it.

    Thing is, I never had these issues before I went EFI. So could it still be the ignition or distrubutor?

    Not sure what pump came with the EFI kit.

    Thing is the car starts each time without issue, just when I'm driving I feel it hesitates, and on 2 occasions today, died on me, after which i put her in P and fired her up again without issue. Strange

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  6. JonnybravoM3

    JonnybravoM3 Member

    You mention some fluctuation isn't abnormal but it is abnormal for the car to die on you right? Or is that part of the package! Not sure haha

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  7. Horseplay

    Horseplay I Don't Care. Do you?

    Stalling out is not typical. At least from my experience and all I have read of others installs but that doesn’t mean it can’t happen and is a sign of trouble or won’t go away once it learns enough.

    I mention the ignition because a single point dizzy has never been ideal. They work but that’s about it. You start making changes and power increase etc and they can lack the “umph” to work the best. A multispark electronic system will be sure to fire the fuel
    Moisture much better.
  8. Mach1 Driver

    Mach1 Driver Active Member

    Are you using the Fuel Command Center or an external pump or an in tank pump? Do you have a return line? Is the tank vented? Like Terry asked- what is the fuel pressure? Unless you didn't do the install you must know what distributor you have. The install is different for a points distributor or one with magnetic pickup- so which system did you wire it for? No offense intended, but you are going to have to provide a whole lot more information if you want help. As Terry said the magnetic pickup type is much better for an EFI- that way it gets a clean tach signal. BTW, most people suggest that you don't let the EFI control the timing initially. Let it learn and then switch over later if you like.
    I just recently read a horror story about FiTech tech support, but it's their system and you really need to talk to them. Let us know how it turns out.
  9. JonnybravoM3

    JonnybravoM3 Member


    Some snaps I just took. I'll start the car and post pictures of the hand held readings.

    This is the kit that I bought and installed.


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  10. JonnybravoM3

    JonnybravoM3 Member

    Hand held at idle [​IMG][​IMG][​IMG][​IMG]

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  11. JonnybravoM3

    JonnybravoM3 Member

    Any recommendations if I was to change the distributor? Would I need to reset and reinstall the system then? The Tech on Summit chat just now said he doesn't think the EFI is designed for a points distrubutor... I'm guessing that's the one I have, the original oem.

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  12. David67

    David67 Active Member

    Why don't you try a pertronix points conversion. It's cheap before you go spending money on a new distributor.

    Sent from my Pixel XL using Tapatalk
    JonnybravoM3 likes this.
  13. JonnybravoM3

    JonnybravoM3 Member

    Hi thanks, not sure what that is?

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  14. Grabber70Mach

    Grabber70Mach Well-Known Member

    It's a electronic replacement for the points that installs in a stock distributor.

    JonnybravoM3 likes this.
  15. JonnybravoM3

    JonnybravoM3 Member

    Thank you. I just chatted with the tech at Summit again, he contacted FiTech while I waited.

    They said the best option for me would be Pertronix Ignite ignition conversion (PNX-1281DV) and a coil (PNX-40011)

    He gave me an option for vacuum advance and one without. I assume my distrubutor has vacuum advance? (pic attached).

    Thanks guys!

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    Last edited: Mar 23, 2018
  16. Horseplay

    Horseplay I Don't Care. Do you?

    You can get a Pertronix conversion (the parts listed from Summit) and greatly improve your distributor performance. You don't have to get a new dizzy but a new full blown Pertronix billet piece with an Ignitor III is pretty sweet. I have one in both engines for my car. :)

    Yes, yours is vacuum advance and a new one should be too for your application.

    I will check my data as set up on mine but I think I see something in your pics that could use a tweak.
    JonnybravoM3 likes this.
  17. JonnybravoM3

    JonnybravoM3 Member


    So I've just ordered this

    And this

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  18. Horseplay

    Horseplay I Don't Care. Do you?

    I just got home after being out all week so haven't fired the car up but here is a very helpful video you need to watch. Also search the Web looking up FiTech and IAC steps.

    You need to get it under 10 when engine is warm. I got mine to like a setting of three as I recall. This one adjustment made a HUGE difference in how my engine ran. There are a lot of other little tweaks you will end up doing likely as you learn more but this is a big one.
    JonnybravoM3 likes this.
  19. JonnybravoM3

    JonnybravoM3 Member


    Turns out that the pump had a loose connection. But, I need your help please with placement, instructions say that it just be placed as close as possible to the tank and along the same level as the base of the tank. That said, where have you all placed your pumps? Trying to find a suitable spot! Any help or pictures would be greatly appreciated!



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  20. Horseplay

    Horseplay I Don't Care. Do you?

    Electric pumps are designed to PUSH not PULL the fuel. This is why it always states to put them as close to the tank as possible. Absolute best location is in the tank itself but this requires more investment in the system, obviously. The largest advantages in such a set up are the fuel itself acting as a cooling agent for the pump and secondly, in a properly designed tank arrangement the pump is located in a baffled chamber which keeps the pump pick-up completely submerged in fuel even under hard corning or braking situations. Nothing worse for a pump than being starved for fuel and run dry.

    My set-up is in tank. If you are going with an external to the tank pump, I suggest mounting it directly in front of the tank opposite the stock sending unit area, as low as possible on the floor pan sheet metal. Be mindful of exhaust routing as you do not want to get any closer than necessary.

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