The present disclosure is directed to injectors with integrated igniters providing efficient injection, ignition, and complete combustion of various types of fuels. These integrated injectors/igniters can include, for example, insulators with adequate mechanical and dielectric strength to enable high-energy plasma generation by components that have very small dimensions, multifunction valving that is moved to injector multiple bursts of fuel and to induce plasma projection, a fuel control valve at the interface to the combustion chamber for the purpose of eliminating fuel drip at undesired times, and one or more components at the interface of the combustion chamber for the purpose of blocking transmission of combustion sourced pressure.