If you are using a factory harness and are after an easy ECU upgrade, take a look at Haltech Plug 'n' Play Adapter Kits. These adapters plug directly into your Haltech ECU and have a set of factory connectors on the other side which plug straight into the factory harness.

A simple Haltech Plug 'n' Play product that allows you to be up and running in just a few hours.

The quick start guide will walk you through installation of the Haltech Plug 'n' Play adapter into your vehicle.

Suits: Plug 'n' Play replacement of the factory ECU for Mazda Miata (MX-5) NA 1.6L and 1.8L with 2-plug, 2-row factory ECU. Manual transmission only.

Includes: Injection molded plastic plug 'n' play adaptor harness, M14 x 1.5 air Temperature Sensor with matching plug and pins, auxiliary I/O 16 Pin Tyco plug and pins.

Notes: Does not support USDM OBDII 96-97, Special Edition SE and Anniversary models. All manual transmission 1.6L variants will require the factory throttle position sensor to be unplugged and removed. A full-range throttle position sensor alternative must be installed for correct functionality. Failure to do so will result in erratic behavior of the ECU at wide-open throttle along with damage to the ECU.