A pressure responsive spring valve which is able to function at high pressures and temperatures, and can attain a high degree of precision control in a minimum of space, as well as an improved high pressure fuel injector for internal combustion engines which uses such a spring valve to achieve the demanding performance characteristics of the more complex new injector designs within limited space requirements. In all cases, a band-like spring valve member is used to reduce the number of parts and the space requirements therefor relative to that required for a coil spring type pressure control valve. Furthermore, whether a split or continuous ring type spring member is used, in accordance with preferred embodiments, by giving the spring member a configuration which is different from that of the circumferential wail of the valve body on which it sits, while producing a matching of their surfaces in the area of the outlet port(s) of the valve member, higher pressures and precision factors are achieved since the spring force of the spring member is concentrated at the port area(s).