Crank sensor changed in my driveway. CASE learn?
#22
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Originally Posted by Gumball
and
<--- this fool showed up late![Embarassed](https://www.gmforum.com/gm/images/smilies/icon_redface.gif)
<--- this fool showed up late
![Embarassed](https://www.gmforum.com/gm/images/smilies/icon_redface.gif)
my phone rings..
Jim: where are ya
Me: at wal-mart
Jim: what are you doin at wally world, im at your house
Me: we've been done for 2 hours and bill went home already - you missed it
way to call ahead jim! lmao
#23
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LOL...Jim called me about 7 hours too late for a meet up...
C'mon Jim..with Aaron and I on the case...the parts are gonna give up quick.
C'mon Jim..with Aaron and I on the case...the parts are gonna give up quick.
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Jim move slow when he doesn't have any beer in him
and when he does, he moves REAL fast down those Stairs
![Laughing](https://www.gmforum.com/gm/images/smilies/icon_lol.gif)
and when he does, he moves REAL fast down those Stairs
![Laughing](https://www.gmforum.com/gm/images/smilies/icon_lol.gif)
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Originally Posted by Cheetah
Do we have pics ![Very Happy](https://www.gmforum.com/gm/images/smilies/biggrin.gif)
![Very Happy](https://www.gmforum.com/gm/images/smilies/biggrin.gif)
and so far so good, car hasn't hiccuped at all since the change. And it feels a bit more confident at low rpms. i think there was some serious timing issues going on making it feel boggy under load at low rpms
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Originally Posted by willwren
Have you considered a case learn? Isn't that required after a crank sensor change?
edit: just looked in the book, and it is recommended
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My understanding was that it relates to the 'match' of the CS and the PCM. So any engine change or CS change would matter. I'm assuming there'* a slight variation in CS sensitivity from sensor to sensor, or perhaps the install position/slop?
Let the experts correct me........
Let the experts correct me........
#30
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CKP Variation Learn:
Eliminate False Misfire DTC'*
Drivability technicians have experienced learn and relearn procedures for years. The Crankshaft Position Variation Learn Procedure — concerning the relationship of the Crankshaft Position sensor or CKP to the crankshaft reluctor — was introduced in 1997 and has been used more broadly since 1998.
DTC P1336 indicates that CKP System Variation is not learned. This learn procedure is needed to compensate for minor variations in manufacturing tolerances that might alter the relationship of the crankshaft position sensor to the reluctor wheel, possibly resulting in a false misfire DTC and MIL illumination.
CKP positions must be relearned when any of these parts are removed or replaced:
CKP sensor
Front cover or bracket holding the crankshaft position sensor
Target wheel (reluctor)
Crankshaft
Engine block
Engine assembly
PCM
The crankshaft position system variation learning feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, the crankshaft balancer interrupter rings, and the crankshaft position sensor Hall Effect switches. The calculated error allows the PCM to accurately compensate for reference period variations. The crankshaft position system variation learning feature enhances the ability of the PCM to detect misfire events over a wider range of engine speed and load.
The crankshaft position system variation values are stored in the PCM non-volatile memory after the crankshaft position system variation learn procedure has been performed. DTC P1336 set indicates that the crankshaft position system variation values have not been stored in the PCM and the crankshaft position system variation learn procedure must be performed. The learn procedure is required after the following service procedures have been performed, regardless of whether or not DTC P1336 is set:
1. PCM replacement
2. Engine replacement
3. Crankshaft replacement
4. Crankshaft balancer replacement
5. Crankshaft position sensor replacement
6. Any engine repair(*) which disturbs the crankshaft/harmonic balancer to crankshaft position sensor relationship
Conditions for Running the DTC
No CMP or CKP sensor DTC(*) set.
Coolant temp greater than 70º C.
Conditions for Setting the DTC
Crankshaft position system variation values are not stored in the PCM memory.
Action Taken When the DTC Sets
The PCM will illuminate the MIL during the first trip in which the diagnostic test has been run and failed.
The PCM will store conditions which are present when the DTC sets as Freeze Frame and Fail Records data.
Conditions for Clearing the MIL/DTC
The PCM will turn the MIL “OFF” during the third consecutive trip in which the diagnostic has been run and passed.
The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
The DTC can be cleared by using the Scan Tool Clear Info function or by disconnecting the PCM battery feed on some models.
If a PCM is swapped from one vehicle into another, the CKP position variation must be relearned also (unless the PCM will be returned to the original vehicle). If a PCM is swapped without a CKP learn, the P1336 will not set and it is possible that a misfire DTC in the P0300 group might later set falsely. This is due to an incorrect CKP position value being stored in the PCM and being used in misfire calculation.
CKP variation is only relearned with a scan tool. It does not relearn “by itself.”
Make sure no DTCs are set. If DTCs
are set, service them before performing the procedure.
The service brake must be firmly applied and the transmission in Park for an automatic or Neutral for a manual.
A/C must be “OFF” and the hood closed.
At this point, use the scan tool and select CASE Learn:
Open the accelerator to the CASE fuel cutoff speed and release it as soon as the PCM cuts off the fuel and the engine begins to decelerate.
The scan tool will identify when the procedure is complete.
Eliminate False Misfire DTC'*
Drivability technicians have experienced learn and relearn procedures for years. The Crankshaft Position Variation Learn Procedure — concerning the relationship of the Crankshaft Position sensor or CKP to the crankshaft reluctor — was introduced in 1997 and has been used more broadly since 1998.
DTC P1336 indicates that CKP System Variation is not learned. This learn procedure is needed to compensate for minor variations in manufacturing tolerances that might alter the relationship of the crankshaft position sensor to the reluctor wheel, possibly resulting in a false misfire DTC and MIL illumination.
CKP positions must be relearned when any of these parts are removed or replaced:
CKP sensor
Front cover or bracket holding the crankshaft position sensor
Target wheel (reluctor)
Crankshaft
Engine block
Engine assembly
PCM
The crankshaft position system variation learning feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, the crankshaft balancer interrupter rings, and the crankshaft position sensor Hall Effect switches. The calculated error allows the PCM to accurately compensate for reference period variations. The crankshaft position system variation learning feature enhances the ability of the PCM to detect misfire events over a wider range of engine speed and load.
The crankshaft position system variation values are stored in the PCM non-volatile memory after the crankshaft position system variation learn procedure has been performed. DTC P1336 set indicates that the crankshaft position system variation values have not been stored in the PCM and the crankshaft position system variation learn procedure must be performed. The learn procedure is required after the following service procedures have been performed, regardless of whether or not DTC P1336 is set:
1. PCM replacement
2. Engine replacement
3. Crankshaft replacement
4. Crankshaft balancer replacement
5. Crankshaft position sensor replacement
6. Any engine repair(*) which disturbs the crankshaft/harmonic balancer to crankshaft position sensor relationship
Conditions for Running the DTC
No CMP or CKP sensor DTC(*) set.
Coolant temp greater than 70º C.
Conditions for Setting the DTC
Crankshaft position system variation values are not stored in the PCM memory.
Action Taken When the DTC Sets
The PCM will illuminate the MIL during the first trip in which the diagnostic test has been run and failed.
The PCM will store conditions which are present when the DTC sets as Freeze Frame and Fail Records data.
Conditions for Clearing the MIL/DTC
The PCM will turn the MIL “OFF” during the third consecutive trip in which the diagnostic has been run and passed.
The history DTC will clear after 40 consecutive warm-up cycles have occurred without a malfunction.
The DTC can be cleared by using the Scan Tool Clear Info function or by disconnecting the PCM battery feed on some models.
If a PCM is swapped from one vehicle into another, the CKP position variation must be relearned also (unless the PCM will be returned to the original vehicle). If a PCM is swapped without a CKP learn, the P1336 will not set and it is possible that a misfire DTC in the P0300 group might later set falsely. This is due to an incorrect CKP position value being stored in the PCM and being used in misfire calculation.
CKP variation is only relearned with a scan tool. It does not relearn “by itself.”
Make sure no DTCs are set. If DTCs
are set, service them before performing the procedure.
The service brake must be firmly applied and the transmission in Park for an automatic or Neutral for a manual.
A/C must be “OFF” and the hood closed.
At this point, use the scan tool and select CASE Learn:
Open the accelerator to the CASE fuel cutoff speed and release it as soon as the PCM cuts off the fuel and the engine begins to decelerate.
The scan tool will identify when the procedure is complete.
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