LS7 Hot Start Issue
I have a cam'ed C6Z that has some transient idle instability immediately after a hot start. Cold starts don't have this idle oscillation.
The ECM has not been AutoVE'ed as yet - I'm waiting patiently for BB flashing to be finished since I don't have a Windows laptop. I've been borrowing one for occasional flashing. This ECM has been flashed with a generic cam'ed tune.
I've attached an image that shows the hot startup to and just past the transition from open to closed loop. I've also attached the log this came from.
One issue with 7.5 logging of fuel status is that it displays closed loop fault status as 'unknown'. BBLogging shows this as 'CL-fault' This car has headers and I've noticed that sometimes closed loop fuel status is logged as CL and sometimes as CL-fault. I'm assuming this is due to the ECM getting confused about the status of the post cat O2 sensors. I have the MIL for both of these DICs turned off. I've logged both pre cat O2 sensors and these are working fine and closed loop operation seems fine so the fact fuel status is reporting 'unknown' doesn't seem to be an issue.
The car has dual LC1's installed and these are both logged as serial PIDs.
The attached image shows that RPMS oscillate several times before stabilizing. It shows the commanded AFR oscillating more or less in sync with RPMS. MAP oscillates out of sync with RPM. I'm not clear what is going on here. Any clue's would be appreciated.
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