evap test NEVER completes
#1
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evap test NEVER completes
anybody know anything about the evap system?
what should I start looking at? testing? replacing?
I am trying to determine if it's part of the A/F wackyness I see when getting on and off the throttle.
thanks!
what should I start looking at? testing? replacing?
I am trying to determine if it's part of the A/F wackyness I see when getting on and off the throttle.
thanks!
#2
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Could be an air leak of some sort.
Once I had a problem with the PCM, it coughed up a
CKP relearn not done code and refused to to the relearn
with EFILiveV6Pro. But no other codes. Dealership took
it in and replaced some fuel tank pressure gizmo and
did the relearn for me under warranty. I don't know why
no EVAP code surfaced but that's the way it went.
If you have a loose gas cap or other air leak into the
tank then the purge will continuously draw fresh and
unmetered air, this would be a variable lean error that
comes & goes w/ EVAP purge on/off.
I think you bop between different idle cells based on
purge on/off but suspect purge is inactive when off-
idle. There might be a PID that shows EVAP purge state.
But off-throttle wackiness also might be the DFCO or
just a way-whacked low-MAP VE, low-airflow MAF cal.
Once I had a problem with the PCM, it coughed up a
CKP relearn not done code and refused to to the relearn
with EFILiveV6Pro. But no other codes. Dealership took
it in and replaced some fuel tank pressure gizmo and
did the relearn for me under warranty. I don't know why
no EVAP code surfaced but that's the way it went.
If you have a loose gas cap or other air leak into the
tank then the purge will continuously draw fresh and
unmetered air, this would be a variable lean error that
comes & goes w/ EVAP purge on/off.
I think you bop between different idle cells based on
purge on/off but suspect purge is inactive when off-
idle. There might be a PID that shows EVAP purge state.
But off-throttle wackiness also might be the DFCO or
just a way-whacked low-MAP VE, low-airflow MAF cal.