Recently I notice a louder than usual ticking noise from the fuel pressure regulator area. It's louder than the normal fuel injector tick and if i stick a screw driver to hear the FPR, the noise seems to come from there. However, searching on evom as well as google doesnt seem to return any concrete help. The FPR shouldnt make that noise so its probably some other place transmitting the noise? The only fuel related mod I have is a Walbro 255 (I have an Evo 8). The frequency of the tick also increases when i rev up the engine.

Any help is much appreciated. Thanks.

 

Its connected to metal so anything can cause noise and it will transmit through the metal. While running disconnect one injector at a time and if it goes away then its that injector, if not then I would say lifter/rocker tickwhich is known on these motors especially with bigger cams...only leave the injector unplugged enough to check for the sound obviously

 

Dump in some injector cleaner with your next fillup.