Are no stupid questions, only stupid answers. Fuel accumulator pressurizes the system until RPM relay kicks in. Is basically a can with spring loaded diaphragm. Diaphragm eventually leaks (is a hose underneath looping back to fuel return line), leading to no pressure until pump engaged. No problem then starting cold because cold start valve compensates enough. Problem is starting hot -- cold start valve inactive on a warm engine (thermistor switch). Can force cold start valve on with warm-up regulator circuit (always 12v), but car of course not driveable like that. BTW: could JZD have picked a LESS accessible place to put the thing? Bill Robertson #5939 >--- In dmcnews@xxxxxxxxxxxxxxx, id <ionicdesign@xxxx> wrote: > i have a stupid question and i should know this but what does a Fuel Accumulator do > exactly? > > mark