MegaSquirt Stimulator v2.2 – Unassembled Kit
MegaSquirt Stimulator v2.2 – Unassembled KitMegaSquirt Stimulator v2.2 – Unassembled Kit

MegaSquirt Stimulator v2.2 – Unassembled Kit

5 out of 5 based on 11 customer ratings
(11 customer reviews)


In stock

SKU: MSStim22-K Categories: , Brand:

Product Description

MegaSquirt Stimulator Board v2.2 – Unassembled Kit; Part # MSStim22-K  (For all versions of the MegaSquirt, PCB 2.2, 3.0, and all surface mount 3.57 boards)

The MSStim22-K includes all the parts you need to build a Megasquirt Stimulator version 2.2 as shown in the picture below:

MegaSquirt Stimulator v2.2 - Assembled Unit


The Stimulator board allows you to fully bench-test all standard inputs and outputs on your MegaSquirt unit. It will apply power to the MegaSquirt ECU and allow you to simulate engine sensor inputs such as a basic ignition system RPM signal, the Intake Temperature Sensor, the Coolant Temperature Sensor, Throttle Position Sensor and the Oxygen Sensor. You can manipulate these signals via the potentiometer knobs on the stimulator to simulate different engine running conditions.

During assembly of your MegaSquirt ECU the stimulator is VERY highly recommended. The assembly documentation will actually direct you to use the stimulator to test the ECU at several points during assembly, allowing you to detect any issues before you move on while they are still easier to find and correct.

After assembly, or if you buy a pre-assembled ECU, the stimulator will help you to get familiar with the MegaSquirt and the tuning software before ever attempting to install the ECU on your engine. This is also an excellent tool for testing your Megasquirt ECU while you are working through building your wiring harness. While not an essential or required tool it is highly recommended. If you don’t purchase a stimulator for yourself you should at least make sure you know someone who has one that you can borrow if needed.

You may have noticed that we now carry two types of Stimulators, this one and the JimStim. The classic Stim works for many traditional ignition setups – fuel control, most distributors, and Ford EDIS. The JimStim adds new functions to deal with newer distributorless ignitions, including being able to simulate missing tooth wheels and test multi-channel ignition outputs. No matter what ignition you have, we’ve got something in the lineup to test it.

Click HERE if you’d like a power supply for your stimulator (no more batteries)

Understanding the MegaStimulator v2.2

There are 5 LEDs on the Stimulator, and 3 on the MegaSquirt. On the Stimulator, the 5 LED’s are:

  • IG (pin 36 Ignition Output) – lights when the ignition is fired on pin 36.
  • I2 (Injector #2) – lights when the second injector bank is grounded [injectors firing].
  • I1 (Injector #1) – lights when the first injector bank is grounded [injectors firing].
  • PMP (Fuel Pump) – lights when the fuel pump relay is grounded.
  • IDL (Fast Idle) – lights when the Fast Idle solenoid is activated.

On the MegaSquirt, there are three LEDs, which are:

  • Injectors – lights when either injector bank is instructed to be grounded [firing].
  • Warm Up Active – lights when Warm-up Enrichment (WE) is activated.
  • Accel Enrich Active – lights when Acceleration Enrichment (AE) is activated.

These LEDs all do separate things.

The Injector LED on the MegaSquirt lights when either Injector bank is commanded to fire, while the injector LEDs on the Stimulator light when each injector bank actually is grounded. The MegaSquirt LED will flash synchronously with the Stimulator Injector LEDs in simultaneous mode, and will flash twice as fast as either LED in alternating mode.

The Warm-up Enrichment values are separate entries in the software from the Fast Idle Threshold value, so these two LEDs will generally light at different, though similar, coolant temperatures.

The Fuel Pump LED is light whenever the fuel pump relay is grounded. Since the Stimulator puts out about 1 pulse per second minimum, and the MegaSquirt leaves the pump on for 2 seconds after the last ignition event, the fuel pump LED should be light whenever the Stimulator is plugged into the MegaSquirt.

By using these LEDs, and adjusting the RPM, coolant and air temperature, EGO, and throttle potentiometers on the MegaStimulator, while viewing the PC Configurator or MegaTune tuning software, you ought to be able to test every function of your MegaSquirt, except MAP function [for which you can suck and blow].

Power supply requirements:

  • 1 – 9V battery or a DC adapter meeting the following specifications:
    • 12 volts
    • 300 mA or greater
    • P5 plug
    • Center positive polarity.

11 reviews for MegaSquirt Stimulator v2.2 – Unassembled Kit

  1. 5 out of 5


    Great product and pretty clear directions. I’ve never assembled anything quite like this and I would give it a 2 out of 5 for difficulty. Something anyone can really do as long as they are competent in following directions. I would recommend!

  2. 5 out of 5


    Awesome kit!! Everything perfectly labeled. Anyone with minimal experience and who has read through the megamanual should have no problem identifying components and getting the unit together. Shipping was cheap with insurance and was delivered to me very fast. Looking forward to doing future business with diyautotune.

  3. 5 out of 5


    You will not need any instructions to build this simple TOOL !

  4. 5 out of 5


    SUPER easy to assemble! SUPER quick shipping. I will buy all my megasquirt supplies only from DIYautotune!

  5. 5 out of 5


    Exellent product! SOOOOOO easy to assemble! great delivery time! I will buy more from this guy be sure!

  6. 5 out of 5


    Great product, Great service, and easy to assemble! If you have never done anything like this before, but have the right tools, and a little patience….you will have no trouble. I highly recommend you start here…it easy and will build you confidence.

  7. 5 out of 5


    Very nice kit, easy to assemble, great service and SUPER FAST shipping!! Thanks

  8. 5 out of 5


    great products, great prices, FANTASTIC customer service and super fast shipping.

  9. 5 out of 5


    The product quality and service I have received from this company is excellent. After buying a Megasquirt I kit from another vendor and waiting 8 weeks to receive it with no direct communication from the vendor it was a joy to have my order for a megastim from DIYAutoTune delivered in less than a week. I have since bought another Megasquirt kit from here and got the same great service. I highly recommend DIYAutoTune.

  10. 5 out of 5


    again i bought this off of ebay……

    no electronic expertise at all……. pretty good mechanically…..

    this was too easy after doing the ecu……. i was kind of bored…..

    just double check yourself a couple times…..

  11. 5 out of 5


    I am a reasonably handy guy, and fairly good with computers and such. Still, when I ordered this kit, I had in the back of my mind, “Gee, do they make a book ‘assembling electronics for dummies?”
    Well, I have to say, after getting and building the kit, if I needed extra help, it would have to be from a book like ‘assembling electronics for complete morons who shouldn’t be allowed to drive a car.’
    The kit is VERY, no, EXCEPTIONALLY well put together. If you have NEVER done anything like this, if you take your time, you can do it. The ONLY way it could be easier is if Jerry held your hand while you did it!
    I could not complain about this if I wanted to. No wait, I can. I am a little older, and Jerry uses a several colors of ink on his lables. The light colors are hard for me to see and I need to use my “extra” strong glasses, (not just the regular reading glasses which are different than the computer glasses,…) Oh wait, I shouldn’t blame Jerry for my lack of close up detail vission. Oh, what the heck, I will blame him! Jerry, use bigger fonts and darker ink!
    But seriously, while I know there are other sources to buy these goods, I will continue to buy them here. No one could do any better, and that’s no joke. Good people are hard to find, these are good people and give you every bit of your money’s worth.
    Tom Stark

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What applications call for a JimStim, and when can I use a regular Stim instead?

  • The regular (V2.2) Stim can be used for installs when you are using just fuel control, a simple distributor, or a Ford EDIS ignition. The JimStim can do all that plus simulate missing toothed crank triggers, distributorless ignitions, and test considerably more inputs and outputs. We recommend using the JimStim if you anticipate that you might need any of these capabilities.