VEMS Miata NA Direct Plug-In ECU

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  • $1,245.00
  • Regular price $1,499.00
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You're going to want to feel how much more alive the engine is with our standalone. Even on a 100% stock car it makes the difference between feeling flat and boring to lively and exciting. If your car is modified, there's no real practical limit to where you can go. 

Upgrade your car with our fully programmable ECU in a matter of minutes without any wiring nightmare.

Designed to be a plug-in replacement for your 1990-1992 Miata. 

The included 4bar MAP sensor is great for normally aspirated cars and perfect for boosted applications.  


ECUs are made to order. 2-3 weeks for shipping typically. Send us a message at info@vems.com if you have a time sensitive need to see what the current lead time is. 


Add order comments on your setup (engine model, injector size, turbo/NA/supercharged, etc.) and we'll provide a base map that will start the car or be very close to starting. Remote tuning is available if you want us to complete the entire tuning process. 


For best results, we recommend Fuel Injector Clinic injectors (click on size for link to product)

Rated size Flow at 3.5bar (stock m52 fuel pressure) WHP 93octane WHP e85


758 553 425


904 659 506


1167 851 653


1400 1020 785


1680 1224 942


2508 1827 1406

or Injector Dynamics (available here: https://shop.vemstuning.com/products/injector-dynamics-1050x-set-of-6-60mm-length)

We recommend against Fuel Injector Connection and Siemens Deka, and any Chinese clone injectors. Fuel is the lifeblood of your engine. The only component more important than fuel is your crank trigger. 


  • Fully programmable control of your engine
  • Integrated wideband controller
  • Control of individual fuel injectors and ignition coils *with added wiring, the stock wiring harness only has 2 coil and 2 injector channels.
  • Control of the idle valve
  • Uses stock sensors (Except intake air temp sensor)
  • You must unplug the AFM, so it can be removed to make intake plumbing less complicated
  • Easily tune for head work, cams, different pistons, etc.
  • Gives the control needed to add a turbo
  • Launch control
  • Anti-lag
  • Boost control by gear or speed
  • 16 free pins of the 34 pin extra function connector
    • 5 analog inputs for sensors or switches
    • Second wheelspeed sensor input
    • Low power output for LED, transistor switching, etc. Max 300mA
    • 4 high power outputs (boost control solenoid,  etc.)
    • Second serial port for digital dash or other expansion
  • Serial port is wired with power for Bluetooth or Wi-fi modules
  • User upgradable firmware
  • Excellent, user-friendly tuning software (http://www.vems.hu/vt/)

This kit includes:

  1. ECU
  2. 4bar MAP sensor
  3. Pre-Calibrated Genuine Bosch LSU4.9 Wideband Sensor
  4. BMW TPS
  5. TPS Mounting Adapter
  6. TPS Wiring Adapter
  7. GM open-element IAT with extension harness to AFM connector
  8. Documents


By default comes with the LSU4.9 plug. If you prefer LSU4.2 just make a note in the order comments and we'd be glad to adjust that for you.

Quick steps:

  1. Disconnect Airflow Meter (AFM)
  2. Connect IAT extension to the AFM plug
  3. Remove throttle body and OEM throttle position sensor. Install adapter and new TPS with wiring adapter
  4. Remove the factory ECU 
  5. Run the wideband extension/adapter to near where the wideband sensor will be
  6. Remove the factory O2 sensor and Install the new Bosch wideband sensor in the exhaust
  7. Plug in the engine wiring harness to the new ECU 
  8. Run a vacuum line to the external MAP sensor. Locating the sensor in the ECU compartment is suggested, but not mandatory 
  9. Connect to the serial port with your computer and turn the ignition on, Connect to the ECU.
  10. Once connected to the ECU with VemsTune, calibrate the TPS (Tools-> TPS Calibration Wizard)
  11. Start the car


Unboxing video: https://youtu.be/afFN2hFyv_U


Intake Air Temp/Manifold Air Temp sensor considerations (IAT/MAT):

  • If you are forced induction, we suggest installing the IAT in the intake manifold or as close to it on the charge piping as practical. We suggest the sensor point slightly down so condensation doesn't collect in the sensor. If you need a replacement, most parts stores will have them, or we have them available as well.  IAT Sensor Only


If you don't already have a tuner lined up, it's a great idea to consider our remote tuning offer. Remote tunes can typically be finished up within 2-3 days with log reviews or in a few hours with a remote dyno session. Available here: https://shop.vemstuning.com/collections/tuning/products/vems-standalone-remote-tune