Thermo timer [Brown plug] under intake manifold....also water temp sender [Yellow plug]....also Auxillary air control [ Black plug]...all under manifold, also the Thermo timer also has 50 starter circuit at it, this allows only about 4 attemps to activate the 5th injector, it then cuts out needing around 4 mins to reset..... so as not to fill the manifold with Fuel, you see after the 5th injector fires the engine, the metering control takes over. Peter.