Glad that I could help. I know what it's like to try to prioritize what needs to be done now
vs what can be deferred, and then when you go out on the internet you see all these
conflicting claims of why it must be done asap, stealerships charging $$$ to clear this
code in a couple of minutes, etc...while others just slap in a new part and have no further issue?
Copy that. I concur with your conclusion, sounds like your Closed Loop setup is working as designed,
taking the Open Loop starting point and learning/compensating around parts still serviceable yet no longer
in assembly line fresh condition.
In some of the EFI tuning forums it's been stated that the CASE relearn does not affect daily operation, but
instead is only used to accuratize the cylinder misfire reporting algorithm. On the other hand, I have read
conflicting reports that it *did* either clear phantom misfire counts or actually improved the driveability of
the engine?
For what it's worth I'm going to experiment on my own '99 C2500 with the Vortec big block. I currently
have no SES light, and using the existing CMP & CKP sensors I will set the CMP retard to 0°. Then I will
change the CKP sensor, and then recheck the CMP retard value. IF there is no change in this sync measurement,
then that will be my first discovery. I'll then proceed to monitor the fuel trims, misfire counts, timing advance
at 65mph, etc., and try to come up with a usable baseline.
And then finally I will perform a CASE relearn, and gather the same data again.
If there's no observable change, then I guess I'll have to side with the 'diagnostic only' crowd.
But IF these parameters do change after the CASE relearn, then this would tell me that the
improved CKP signal accuracy is also used to improve everyday operation.
Time will tell. This stuff really intrigues me, and I've decided to
diagnostic bits. Book learning is good, but proving/disproving stuff like this based upon real world
experience is much more gratifying/adds insight to the computer managed side of my internal
combustion belief system. :0)
Anyway, best of luck with your move. And although I don't act in any official capacity in this forum, it's nice
to have you aboard as a fellow Supporting Member. And your moving adventures are good mental practice for
yours truly, for I will also be moving using my truck in the near term. (ie: I want to swap in a
new CKP sensor, for the one in there looks to have been there since it first drove off the assembly line.
If I do this right, I will have a new 'proven-good' one in place, plus a 'tested good' used spare CKP sensor
under the seat, along with a 'tested good' ICM, rotor, cap, etc.)
So thanks for sharing your road warrior stories, for it's gotten me to think a bit more like a prepper and less
like my 25 year old truck simply owes me no downtime on the side of the road because I own the thing. :0)
Safe travels --
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