Postby VStar650CL » Mon Sep 04, 2023 9:23 am
For an injector to cause pressure loss with the key off, one of two things is happening, either one of the o-rings is leaking or the injector plunger is stuck physically open. The supply voltage to the injectors is cut off when you kill the ignition, and the ECM is dead so there's no potential ground either (there's no intermediate module, the ECM drives the ground side of the injectors directly). That means an electrical problem would require a simultaneous failure on both sides of the circuit, which is extremely unlikely.
Did you put in new injectors, or remans? The failure rate on remans is hideous, even from reputable manufacturers. I've seen and heard of many instances where 50% or more of a batch were malfunctioning or DOA. The failure rate on China-cheap new ones isn't zero either, although it's better than with remans.