Megasquirt FAQ

Discussion in 'ENGINE MANAGEMENT' started by Fatman, Oct 11, 2009.

  1. Fatman

    Fatman Registered User +

    In this FAQ I am attempting to cover everything required to assemble, install, configure, tune and enjoy a megasquirt based ECU into your EP82/EP91. Included will be Starlet specific assembly instructions, pinouts required for making your own plug in adapter to the stock wiring loom, Configuration of all the MS2 + Extra features such as fueling, ignition, boost control, nitrous control, launch control and flat shifting and will also be covering how to use additional outputs for things like using an ACIS manifold from a 5E-FHE.

    Hoping to also find the time to write up a slightly more starlet orientated tuning guide to encourage more people to learn and attempt to tune their cars themselves, safely.

    You can help by asking questions! If you have anything you would like to see included then feel free to post it up.

    Megasquirt FAQ

    This write up is eventually intended to be a comprehensive DIY and FAQ document covering every aspect of using a Megasquirt based ECU (be it a preassembled product or a home built kit) on a 4e or 5e engine in the EP series Toyota’s.

    What is Megasquirt?

    Megasquirt is electronic fuel injection controller developed orginally as an educational exercise. It has since been developed and expanded by many individuals to become a very reliable ECU with an affordable price point and a comprehensive feature-set. It has been used on cars of virtually every marque and an enormous variety of engines.

    What do I need to use Megasquirt in my Starlet?

    Most relevant to our use in Starlets are the Megasquirt-II based DIY kits and the microsquirt based DIYPNP.
    The MS-II kit comes as a bare circuit board along with all the individual components required for assembly. A finished unit will take somewhere between 4 and 10 hours to complete depending on familiarity and apptitude with basic soldering and electronics.

    DIYPNP is a kit, but a far less complex one! The general premise is a pre-assembled microsquirt based ECU with a separate daughterboard equipped with a variety of plugs for use with stock wiring looms. The DIY aspect comes with connecting the two. You must wire the MS board to the daughterboard to suit the car the ECU is going into.

    These two products have virtually identical features and both run the same software and are tuned in the same manner, but they are aimed and priced for a different target market. If you’re interested in learning how EFI works and have any experience working with electronics the perhaps the MS2 kit is for you. If you’d rather skip to the tuning and results phase then the DIYPNP kit is a great option.

    How do they cost?

    My vendor of choice is, they carry a large variety of Megasquirt related products.

    DIYPNP - $460 USD

    MS-II Kit - $247 USD
    Along with the MS-II kit you will need the Zeal Dual VR Conditioner daughterboard to use the stock distributor sensors - $35
    18" Wiring loom - $48

    They ship world wide and I have had nothing but excellent experiences with their service, even to the other side of the planet ;)

    Much more coming soon!
    2 people like this.
  2. J25GTi

    J25GTi Paid Member

    cant wait to see this, Brilliant! Repped!
    1 person likes this.
  3. wastegate

    wastegate Paid Member

    i was thinking about them..
    I have seen to their site about is it worth it?
  4. J25GTi

    J25GTi Paid Member

    dependsi f you can build it yourself or not. if not, then probably not,
  5. HutchGlanzaV

    HutchGlanzaV Registered User +

    Looks like it could shape up to be a good read. I would have absolutely no idea how to build an ecu or use it to tune my engine. Its gotta be said dude, your bringing some good (if contraversial sometimes! :p) info to the forum.
  6. J25GTi

    J25GTi Paid Member

    Mine is on order now, its going to be amazing, Megasquirt is one of, if not the best ECU's out there, okay, its time consuming and a bit long winded, BUT, i dont need ot buy a boost controller, it can be built into the MS system.

    it will run launch control, flat shifting (a type of anti lag system) Can run widebands through it, and all sorts, will control nitrous oxide and all kinds of other systems.

    and there is always new circuits been added and you can modify it constantly,t here is always new features been added!
  7. jonny-boi32

    jonny-boi32 Paid Member

    definately some helpful info on here. think when i get some spare 'doe ray me' ill have to invest in one.
  8. wastegate

    wastegate Paid Member

    It has plag n play kit for us???Tercel model is simiral to glanza?In Greece we dont have tercel that's why i dont know..
    Reading specs it has many abilities and for his price its best...
    Compare with ems pro ( ) does it has any difference?
  9. Fatman

    Fatman Registered User +

    Cheers, controversial is definitely not the end of the world :) All going well you'll have a reasonable idea of the basics once I finish writing all this stuff.

    It's a great project and an excellent way to learn more about how your car works. Not to mention you can get some great results at the end of the day.

    Yes, you can buy an ALMOST plug n play kit, the small amount of wiring is very easy to do.

    Tercel's are very similar to the starlets, if there's enough demand I'm happy to include some Tercel specific info. No - there's no significant differences between the EMS pro and an MS2 or DIYPNP. If anything I suspect the kits have better software and more accurate tuning capabilities. The EMS Pro is quite an old design now.
  10. Sheldon

    Sheldon Malta Area Rep.

    you can buy it preassembled.

    @ Fatman, can i use the preassembled one and ask them to add the Zeal Dual VR Conditioner daughterboard ?? as i said before i dont have much time to solder all components myself. i may have time on a weekend to fit it and maybe a week after to run it..

    so buying it ready would be perfect! and cheers for your help :)
  11. Fatman

    Fatman Registered User +

    I should elaborate a little on the parts and prices I have listed, the DIYPNP product does not require the additional VR conditioner as it's already compatible with our ignition requirements out of the box! Were you to buy the DIYPNP I'm very confident you could have it functional within your time frame. There may be some limitations on some of the extra features you can use (e.g Boost control/flat shifting/etc), I need to trawl through the feature comparisons to be sure.

    The MS2 kit works out a little cheaper if you're doing it yourself, plus you have the opportunity to learn a great deal.

    My package from DIYAutoTune turned up today with my boost control solenoids, wideband O2 bungs, stub looms and pair of Dual VR conditioner boards. I also went on a cruise through a couple of local junkyards and found a few things...
  12. Sheldon

    Sheldon Malta Area Rep.

    ic. BUT can i use an MS-II that is already built by diyautotune? as it built the same as you do it? pin outs the same? boost controller feature is great as its just a few quid!! take pics when you do stuff mate:) helps me more as sometimes i dont understand without pics haha
  13. Fatman

    Fatman Registered User +

    Yep - you can certainly buy a pre-built MS2. Although the results are the same, the assembly of the board is quite different, the pre-built options use SMD components and they are much smaller. Adding the Zeal card is a matter of only a few wires and the actual assembly should be quite quick. I'm just about to start putting together one of mine, I will take photos and time the process.
  14. Sheldon

    Sheldon Malta Area Rep.

    isnt the SMD option only on the new one? the SMD PCB 3.57?? and the DIY one is PCB 3.0?
  15. J25GTi

    J25GTi Paid Member

    i think that is correct sheldon, a fully built one should do everything and if you can get them to add the daughterboard to dual VR input aswell you should only need to butcher our loom and add in the MS system to it.
  16. Sheldon

    Sheldon Malta Area Rep.

    plus upload the ms2 extra code to the unit and base map :D
  17. Toyota T23

    Toyota T23 Registered User +

    You guys will love it, been running it for almost 4 years in my starlet, never had problem with it...
  18. Fatman

    Fatman Registered User +

    No loom butchering will be required! You will be able to unplug your stock ECU and plug in the Megasquirt. That is the goal.

    Here are a few photos of last nights progress

    My desk with the components laid out for the Zeal daughterboard, my soldering iron and a few ECU plugs
    Close up of yesterdays find, these are the 3 plug sockets used on the facelift manual and Automatic EP82's and all the EP91's. Conveniently, the two plug cars also work fine with this, you can just leave the third socket unused or cut it off. Yesterday managed to find 4, I think I shouldn't have too much trouble finding more, just time consuming.


    This is the completed daughterboard. This took me about half an hour and was *very* easy. Place the components, solder them on. Nothing tricky in the slightest :) Everything that comes in the kit (or indeed, any kit from DIYAutoTune) was exceptionally well labelled.


    Todays job is completing the EP82/91 to MS pinout diagram and later soldering up a completed harness.

    To all those asking about boost control/flat shifting etc, the parts required are very simple.

    For Boost control you need a compatible boost solenoid, these come stock in many cars and you can probably get a lot of them to work well, however the easiest option is to buy the Boost control mod kit from the same store. I've holding two of them in my hand and they're very solid units. The kit comes with the solenoid, two nipples to suit, a pigtail harness and the mounting hardware.

    For flat shifting/launch control (which are forms of anti-lag) all you need is some sort of input to turn it on. In my case I'm going to be installing a microswitch on the clutch pedal and a master toggle on the dashboard. Hit the toggle to turn on the system, mash the clutch to enable. This will mean on the line at the drag strip all I need to do is select first (or second :p) with the clutch in, mash the loud pedal and I'm starting to build boost. Likewise for flat shifting as soon as I hit the clutch the system takes over and maintains pressure and limits revs between gears.

    For nitrous control you run the solenoid control to the MS rather than to a physical switch. You can then set parameters in the software on when it should enable the nitrous and how much extra fuel to inject and how much to retard timing by.

    Hopefully that answers some more questions.
  19. Sheldon

    Sheldon Malta Area Rep.

    :rockon: keep us posted! great dude..
  20. finx

    finx Paid Member

    nice wright up bro. cant wait to pick up my ms2 and we can start playing with it. the nitrous control is going to be interesting :shoot:

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