555 based fuel injector tester

Makerdino shared his 555 Based Fuel Injector Tester in the project log forum:

I’ve posted this one elsewhere but it’s a work in progress so I figured I’d share it here. I spent about four hours today reworking the schematic and the next step is to make a PCB, solder up the components to it and get it in a new larger enclosure. I’ll probably do another video of the PCB build because I’ll be using the Laser printer technique with a twist of my own involved.

Since I use two 555 timers in this, I plan on entering it in the 555 contest.

I have a video on Youtube which explains a lot of what his project is about.

Via the forum.

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  1. Great D.I.Y!
    How can I use your circuit to control 6 fuel injectors simultaneously? Do I just wire them up series to the output of this circuit? In parallel? I’m concerned about amperage and voltage drop.
    Do I need to use your circuit to control a relay circuit that can handle more current and wire the injectors from it? If so, would that be wired in parallel or in series?


  2. I am building an injection tester that has the capability of hooking up to 12 injector leads with a rotary selector switch to try and expedite my diagnosing. Your sight has opened me up to the realm of what’s possible with some bits n pieces and a little time ,thanks.

  3. Wow this is fantastic!

    Im actually in the process of doing a university project on a fuel injection testing system and this is literally the most amazing creation to me, my electronics skills are not the best to be honest

    I study motorsports technology and would love for you to help me manufacture one of these so it can be used with 4 injectors.

    I would appreciate any help you could provide!


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