Engine Management Systems & Tools






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MegaSquirt Electronic Fuel Injection Systems

Wideband O2 Sensor Systems, Wiring Harnesses and more...

We are Your One-Stop DIY EFI Shop!

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MegaSquirt EFI has gone PRO!

MS3-Pro: MegaSquirt EFI has gone PRO!

Maximum Performance, Maximum Durability, Maximum Featureset.


MS3-Pro takes the Land Speed 240sx to the East Coast Timing Association's 200mph club at the Ohio Mile!

Jerry Hoffmann now holds 13 records at the Ohio Mile in his MS3-Pro powered Nissan, with the fastest at 217.3913 mph!'s LSR 240sx at the Ohio Mile July 2014

Click here for more info on the build of this car, and what's next! 


Who is DIYAutoTune?  What do we do?  How can we help YOU maximize YOUR vehicles performance?

Watch this short video to find out!

  Which EFI System is right for you?  Let us help you decide.
Highly Affordable DIY EFI MegaSquirt KitsPreAssembled MegaSquirt EFI Systems ready to wire and fire!Pro EFI Systems and MSPNP Plug-N-Play Systems for 20min install!


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You'll get info on all of our latest deals/promotions faster than anyone elseas well as a behind the scenes look at new products in development....

Who is DIYAutoTune?

Based in Suwanee, GA (near Atlanta) we are the primary manufacturer and distributor of the MegaSquirt line of EMS/EFI Systems.  Made right here at our facility in the USA.  In short, we offer you an affordable way to run your race car on a fully programmable fuel injection and ignition controller, with plenty of high end features such as progressive nitrous control, boost control, 3 step rev limiters, electronic fan control, and spare outputs to control just about anything!

How can we help you accomplish your goal of running EFI on your ride?  Email us at and let us know!

Everything we build is made right here in the USA, most of it in our Suwanee, GA home base!
Everything we build is made right here in the USA, most of it in our Suwanee, GA home base!

Converting a carb'd engine to EFI?

Check out our 3-part series that shows how to do this very affordably, or a bit flashier if you choose.

      Check out our Bonneville Project!
DIYAutoTune's Land Speed Nissan 240SX Project Blog

Featured Products!


New MS3-Pro!


The MS3-Pro can run a V8 with full sequential fuel and ignition, a V12 with sequential fuel and wasted spark ignition, or a 4 rotor Wankel with separate leading / trailing ignition. It's also got a weatherproof case, heavy duty connectors, and more!


MegaSquirtPNP Pro is here! Our latest release is based on the MS3-Pro and fits the '93-98 Toyota Supra Turbo. Other MegaSquirt PNP models include:

  • '86-'95 Ford 5.0 Mustang

  • '90-'05 Mazda Miata

  • '87-'92 BMW 325i

  • '85-'90 Toyota 4AGE and 22RE

  • '89-'98 Nissan 240SX

  • '93-'95 Ford Probe and Mazda MX6 with V6

  • '90-'95 Toyota MR2 / Celica 3SGTE

There are several more MSPNP applications in development now to be released soon!

Check out the new EFI Book, by our own Matt Cramer and Jerry Hoffmann

Innovate's MTX-L Wideband/Gauge combo

Innovate Motorsports MTX-L Wideband O2 System


Follow us on Facebook / Twitter for new product info & discounts!

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Welcome to  The place on the web for all of your Do-It-Yourself (DIY) automotive tuning needs.  We have everything you need to install your own fully programmable Engine Management System on almost any engine in any car  / truck / motorcycle / boat / snowmobile, you name it!  For the hardcore DIY'er who wants to actually build your own EMS, we've got you covered, for others who'd prefer we build you up an ECU to your specs so you can just worry about the wiring and tuning side of things (with our help of course), we've got you covered too!  We're also added a fairly large number of Plug-n-Play solutions to our line-up... 

Start reaping the benefits of a Standalone Engine Management System (EMS) immediately -- With the ability to dial your engine in for maximum power and performance no matter what modifications you've performed, and when you mod something else, just dial it in-- you don't need to pay someone else to do this for you if you've got a bit of patience and a willingness to read and learn about the system a bit.  It's laid out and made user friendly with the first time EFI tuner in mind, but with the power of an advanced Engine Management System. 

So do our tuning products work with imports or domestics?   YES!'s team are all equal opportunity performance junkies,  we love 'em all and the products we offer will work equally well on any vehicle out there with very few exceptions.  So come on in, check out our Project and Customer Cars, read a bit on the FAQ and see what you think.  Also make sure to check out our 'Which MegaSquirt EFI System is right for me?' section to help you figure out which productline perfectly matches your performance/featureset needs as well as your budget.

You too can 'Tune it Yourself.  Tune it for Less.  Tune it Right.'   The DIYAutoTune Way!


DIYAutoTune FAQ -- MegaSquirt and Wideband o2 Frequently Asked Questions

We're on top of all of the latest tuning products and kits with great products like Bowling and Grippo's MegaSquirt line of DIY Programmable Electronic Fuel Injection systems, and excellent Wideband O2 systems and tuning products from Innovate Motorsports, with our own line of wiring harnesses and accessories to make your project go as smoothly as possible. 

We offer the full line of Bowling and Grippo's MegaSquirt Engine Management Systems in kit form or fully assembled and ready for use.  All of our electronics kits are clearly labeled and include everything you'll need to build your own unit.  Additionally we offer extruded aluminum cases with professionally machined endplates for those of you who purchased your MegaSquirt components elsewhere, as well as the 'old-school' B&G partial kits if you'd like to piece your own kit together.  You can view all we have to offer on our our Online Catalog.  We're adding new stuff all the time, many items at the request of the customer-- we've been your 'One Stop DIY EMS Shop' since late 2004 and we're here for you-- so let us know if there's anything we can do to help you move your project along!


Just a few of our products, check the catalog for full listing


You're used to working with tools right?  So let's put a new tool or two in your pocket, tools that may just be the most powerful you've ever wielded in your quest for automotive performance.  You CAN do this yourself if you want to, and you CAN do it right, the information you need and desire is right here for you-- or if you prefer you can farm the install and tuning out to your favorite shop and just enjoy the benefits, that's up to you.

New to EFI?  Here are a few articles that might interest you.  Don't take our word for it that you need a standalone EMS to extract all of the power possible from your engine, see what the 3rd party articles below have to say about Electronic Fuel Injection and Ignition system control and then let us know how we can help you get on the path to having full control of your engine as well!

DIYAutoTune is an MegaSquirt EMS/EFI manufacturing and distribution company. Our main offerings include: MegaSquirt Plug-N-Play Engine Management System Kit, including several new vehicles, our MegaSquirt-I system, MegaSquirt-II, and MegaSquirt-III Assembled and unassembled versions, both with black cases.




Lee Sicilio takes the A/BGALT Land Speed Record and Frank Kinney takes the E/GMS record at on the Bonneville Salt Flats! 

Lee Sicilio with his 283mph Daytona Charger Both cars run MegaSquirt-3 with MS3X Expansion, gettin' it done! 

Click this link to see more pics and IN-CAR video!
Black Opel Racing in impound after record qualifying run


Bonneville 2012!!

Congrats to Lee Sicilio for his 273.514 mph World Record!

World's Fastest MegaSquirted Car -- 283mph exit speed!

Check out this page for pics and IN CAR video!

James 'Doc' McEntire Wins @ Drag Week 2011 and 2012!

James McEntire MS3X Camaro at Drag Week 2011!

MegaSquirt-III Power!

Congrats to Travis Nordwald for a 1st Place win in the ARRC Enduro ITA Class!

Travis Nordwald's ITA Miata

MegaSquirtPNP Power FTW!



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Performance testing & tuning by LoadStorm.