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MicroSquirt ECU
MicroSquirt ECU
MicroSquirt ECU by DIYAutoTune, MicroSquirt with 30, MicroSquirt with 8
MicroSquirt ECU

MicroSquirt ECU Version 3.0

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(1 customer review )
MicroSquirt ECU Version 3.0



The versatile MicroSquirt ECU Version 3.0 is an ECU plus much more – Standalone Engine Management System, Transmission Controller or CAN I/O Expansion Module (alternate functionality requires firmware change)

MicroSquirt ECU is our entry-level, fully assembled ECU with varied applications targeting power sport and single cylinder all the way up to 8 cylinders with up to 2 fuel and 4 spark outputs. Over 40 different ignition modes are supported from mainstream applications like GM LS1, Ford Zetec, Bosch Motronic, and Chrysler Gen III Hemis to unusual modes like Renix Jeep and the Suzuki Swift GTI.

MicroSquirt ECU Software Features

-Supports speed density, alpha-N (TPS based), or MAF based fuel and spark tables
-0.66 microsecond injector pulse width resolution
-Allows blending multiple load types, including specialized mode for independent throttle bodies
-Supports a wide variety of OEM cam and crank position sensors
-Accelerator pump or model based acceleration enrichment
-Closed or open loop idle speed and boost control -On/off nitrous control
-Wankel rotary support: 2 rotor engines with separate leading and trailing spark tables
-Staged injection
-Table switching
-16 x 16 fuel and spark tables
-2 step rev limiter (launch control) with no-lift shifting
-Wideband AFR target table
-Flex fuel sensor input
-Real time barometric correction (external sensor required)
-Sequential shift cut and air shifter control

MicroSquirt ECU Transmission Control Options

MicroSquirt transmission control free firmware allows you to use MicroSquirt with 30″ Harness to control a number of electronic automatic transmissions (gearboxes). It can work standalone or integrate with one of our ECU’s over canbus.

Control applications: GM 4L60E I GM 4L80E I GM 4T40E I GM 5L40E (dev) I A341E I 41TE (dev) I Ford 4R70W I Ford E40D (dev) I Subaru W4A33 & more…

MicroSquirt ECU CAN I/O Box Expansion

Microsquirt I/O Box firmware allows you to use a Microsquirt as a plug’n’play I/O extension box for MS3 or MS3Pro ECUs. It can offer a useful I/O addition:

-7 Analog inputs (0-5V variable)
-2 Wheel speed inputs (VR or hall type)
-2 Wheel speed (hall type) or ground-switch inputs
-1 dedicated ground-switch input
-2 high current PWM/switch ground-switching outputs
-4 mid current PWM/switch ground-switching outputs
-1 low current PWM/switch 0-12V output
-Perfect for capturing and logging vehicle speed and additional sensor data (e.g. pre- and post- intercooler temperatures, fuel pressure, oil temperature etc.)

To Use a GM 1, 2, or 3 Bar MAP Sensor with the MicroSquirt ECU

In the illustration:

A is ground,
B is the sensor output signal to MicroSquirt,
C takes 5 Volts from MicroSquirt.

The pins are marked A-B-C on the sensor itself.

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1 review for MicroSquirt ECU Version 3.0

    Only logged in customers who have purchased this product may write a review.

    Is this just for motorcycles and other small engines, or can it be used in a car or truck?

    • The MicroSquirt can run regular automotive engines; it’s not just for powersports applications. It is possible to run this on a V8 in wasted spark, although it doesn’t have very much I/O to spare for extra functions when using four spark outputs.

    I’ve heard some people say it has two spark outputs and some say four. What’s the deal?

    • It was originally designed for two spark outputs, but the MS2/Extra code allows you to use WLED and ALED outputs as additional spark outputs. You will need to add resistors in the wiring harness for using them with most coils.

    Is it waterproof?

    • No, but you can make it waterproof with a bit of RTV silicone around the edge of the case.

    Are there other versions of the MicroSquirt for other functions? Transmission control or the “IO Box”, for example?

    • These all use the same ECU, just running different code to change its function and use it as a transmission control unit or I/O expansion device. See for details.

    Could I use two MicroSquirts, one running the engine and one running the transmission?

    • Yes. They would link up over their CAN networks to look like a single unit to the tuning software.

    Where is this unit made?

    • They are built in the USA.

    What do I need to tune this unit over USB?

    Questions & Answers

    1. 0 votes

      The MicroSquirt can run a V6 as long as you use high impedance injectors or suitable current limiting resistors for low impedance injectors. It will support a Nissan optical distributor, or you can add one of our trigger wheels to support distributorless ignition. Idle control can be done with a PWM type (2 or 3 wire) idle air control valve. Please contact our technical support team if you have any questions.

    2. 0 votes
      Q Will I need anythig else for a turbo 351w? answer now
      Asked on March 30, 2018 10:59 am

      This listing is for the ECU only, no wiring or sensors. There are several different ways one could set up a 351W. Please contact our technical support department if you want to go over your build in more detail. We'd be glad to get a recommendation together for your specific build.

    3. 0 votes

      Yes, it can either run fuel-only or control both fuel and ignition.

    4. 0 votes

      Yes, and it will run the stock sensors except that you will want to add a GM type MAP sensor as well as a wideband O2 sensor for tuning. If you are using the 4R70W automatic, you will need to add a second MicroSquirt to operate the transmission.

    5. 0 votes

      The MicroSquirt is a universal ECU and can run a wide variety of engines, including a 5.0 Mustang.

    6. 0 votes

      Yes. If you have the M10 four cylinder, you can either use the stock distributor advance for ignition control and run fuel only or modify the engine for electronic ignition control. For the M20 eta six cylinder, your best bet is to swap to the later M20B25 crank trigger setup to let the MicroSquirt control your timing.

    7. 0 votes

      On a four cylinder, a MicroSquirt can run bank to bank fueling but not sequential fuel control. The engine is likely to run fine on bank to bank fueling although sequential fuel control may give a few improvements to idle control and light throttle drivability. You will probably need a QuadSpark ignition module to fire this coil.

    8. 0 votes
      Q Is it compatible with 4g63 Motors? answer now
      Asked on July 18, 2017 5:38 pm

      A MicroSquirt can control fuel and ignition on a 4G63, no problem. See the 4G63 notes in the MS2/Extra MicroSquirt Hardware Manual for details.

    9. 0 votes

      Current MS2/Extra firmware can use a MAP sensor for phase detection on a V-twin if you are using a missing tooth crank wheel. No cam wheel needed.