On turbo Diesel truck applications, water/methanol injection systems reduce air inlet temperatures and enhance combustion efficiency which allows the engine to deliver more power with less effort. It also offers a host of benefits that promote engine longevity, including the reduction of carbon deposits left by a Diesel's exhaust gas recirculation (EGR) system. AEM's Water/Methanol Injection Systems for turbo Diesel and naturally aspirated HD trucks utilize the most robust hardware combined with more advanced features than any other comparably priced water/methanol system. AEM's on-demand progressive Multi-Input controller for AEM's Diesel Water/Methanol Injection kit features a multiple input design that enables users to install AEM's Water/Methanol Injection Kit on ultra-high boost turbo Diesels (above 40 PSI) using an external MAP sensor. The Multi-Input controller works with an external 0-5v voltage-based external MAP sensor, a frequency based input for Injector Duty Cycle (IDC), frequency-based mass airflow (MAF), or a 0-5v voltage-based MAF to ensure the proper amount of water/methanol injection at all points along the engine's power curve. AEM's engineers spent extensive time developing the HD water/methanol controller's flow control strategy for a more linear flow output delivery. This means that the flow delivery better matches an engine's need for water/methanol injection, which further improves charge air cooling and reduces EGTs. The new HD controller design features large, turn-resistant knobs and larger numbering to easily set accurate start and full activation points, with covered status LED and test buttons for added splash resistance. The Multi-Input controller has an easy-to-remove plug covering the programming dipswitches and a programming legend on the back for the 0-5v and frequency based settings, an easy to access integrated fuse and molded mounting tabs.