first generation of MX-5 NA has switch-type TPS sensor (except cars equipped with AT). Having aftermarket ECU its worth replacing this sensor for potentiometer-type. Improves throttle reaction and also enebles additional functionality like: launch-control and flat-shift. Adapter is necessary:

https://www.thingiverse.com/thing:4773854

suitable sensor BMW 1363 1726 591 or BMW 1721 456

stock connector can be used, but terminal order change is required (repinning) ground signal +5V

 

Update 2025

plug and play solution avaliable at my shop