Well done Richard ! And on face value there doesn't appear a great difference in the good and bad captures . This is one of a techs great challenges interpretation of a dtc . So the signal looks plausable especially as the component being tested is subject to varying conditions . Basically the current and duty didnt match the pcms monitoring so it spat out the dummy.
When ive seen scv,s sticking yes you see an obvious high current draw but not here.
Danny
Exactly what I thought nothing really stands out to me. Maybe the extra 10% duty cycle at certain pressures is taking it out of its "comfort zone".Cannot be sure, I think you would have to check multiple good and bads to secure an answer. The nail in the coffin for me was the hunting at idle and cut out (seen this multiple times on denso systems and fixed it evey time with an IMV) followed by KOEO permanent fault after it had warmed up backed up by bias voltage reaching it all the way down to the IMV. My only regret is not having the scope on it as it failed. I didn't save the bias voltage capture as it wasn't very interesting it was just a quick square waveform just after the ignition was turned on then no voltage or current. Engine would still run but had very limited power
Yes but a curve ball for sure , nothing really jumps out on the waveform , and as rym says the eureka moment came with the surging at idle and stalling ,not at wot I think you would have been analysing the hell out of high and low fuel systems before condemning an imv .
My only thought was to emulate a signal to imv with scope attatched for current and duty and lightly tap the scv body to look for changes .
Danny