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Guess I need case learn?

Posted: Sat Apr 02, 2016 11:42 pm
by ron350
I replaced the crankshaft position sensor in my 96 and now need a case relearn. What are the dealers charging now for the relearn service?

Re: Guess I need case learn?

Posted: Sun Apr 03, 2016 5:49 pm
by SSEBonne4evr
ron350 wrote:I replaced the crankshaft position sensor in my 96 and now need a case relearn. What are the dealers charging now for the relearn service?
Never heard of this, I just unhook the Neg. Battery cable 20 min., re-install and let it re-learn.

Re: Guess I need case learn?

Posted: Sun Apr 03, 2016 6:49 pm
by ron350
This is from an earlier thread on this forum.
http://www.pontiacbonnevilleclub.com/fo ... rn#p368752


CRANKSHAFT VARIATION RELEARN (CASE Learn)

”CASE” means: crankshaft angle sensor error. A crankshaft variation relearn must be performed if:

A diagnostic trouble code of P1336 is present.
The computer has been replaced or re-programmed.
The crankshaft position sensor has been replaced.
The engine, harmonic balancer, clutch, or flywheel have been: disassembled, removed, or replaced.
The crankshaft position variation learning feature enables the computer to compensate for part manufacturing tolerances. This allows the computer to accurately detect an engine misfire throughout the engine RPM range. The learning process is stored in the computer’s memory and does not have to be repeated unless one or more of the above conditions are present.


To perform the relearn, proceed as follows:

Connect a scan tool to make sure there are no trouble codes stored in the computer’s memory. If there is any power train trouble code other than P1336 (Crankshaft Position Variation not learned), the computer will disable the relearn function until the problem that aused the code has been eliminated. Also, make sure that the engine coolant (check it when the engine is cold) and oil levels are at an acceptable level.

1. Set the parking brake and block the drive wheels. Make sure that the hood is closed.
2. Start the engine and make sure that the engine coolant temperature is at least 158 degrees F. (70 degrees C.)
3. Turn the engine off for at least 10 seconds.
4. Select the crankshaft position variation learn procedure (CASE Learn)on your scan tool.
5. Make sure that the transmission is in Park. Start the engine.
6. Apply the brakes and hold the pedal firmly.
7. Follow the scan tool instructions.

Remember: That you are going to increase the engine speed to approximately 3000 RPM, 4000 RPM, or 5150 RPM. That’s the variation learn fuel cutoff RPM (depending upon the engine), and that it’s important to release the throttle when the engine RPM starts to decrease as a result of the fuel cutoff going into effect. Failure to do such will result in over revving of the engine, causing possible engine damage.

8. Once the engine has returned to idle, check the status of Diagnostic trouble code P1336. If the scan tool indicates that the CASE has been learned, the relearn procedure is now complete. If CASE has not been learned, check for the presence of other power train codes. If any exist, correct the problem, then repeat this procedure.

Re: Guess I need case learn?

Posted: Mon Apr 04, 2016 1:50 am
by ron350
SSEBonne4evr you have me wondering if there is a CASE learn for 1996 GM cars.
After a long search I can’t find any mention of P1336 or CASE learn in the 96 factory service manual?

Re: Guess I need case learn?

Posted: Mon Apr 04, 2016 12:18 pm
by SSEBonne4evr
Yes, did you unhook the battery when installing the sensor.
This is standard procedure, most Tech's will tell you so a proper
re-learn may happen.
Maybe someone else will chime in on the case re-learn, if it is applicable.

Do you have a trouble code?

Re: Guess I need case learn?

Posted: Mon Apr 04, 2016 1:37 pm
by CMNTMXR57
You are confusing two things I think and both of which involve Idle re-learns.

What you are referring to is simply a PCM reboot. You're resetting all DTC's, I/M system status monitors and resetting all parameters to their base curves. Basically, you're clearing the cobwebs out of the PCM's brain from learned habits (your driving style, conditions, etc...). This is an idle re-learn. And their is also an optimum driving cycle to get the most out of the relearn process.

What the OP is referring to is more of a resynch of the CKP with the CMP and other inputs. Can I say that it is applicable to his vehicle? Of the top of my head, I'm not sure. It depends on the years, specific models, etc... Some GM vehicles need it, some GM vehicles don't. A lot depends on the PCM and programming/sophistication, other functions that are under control of the PCM (say if you had VVT or other variable functions), etc... In all honesty, if the car is running now, and seems to be fine (I say that assuming you've monitored functions on a scan tool and there are no DTC's, all I/M systems are ok, and that all seems normal), it may not be necessary.

Re: Guess I need case learn?

Posted: Mon Apr 04, 2016 2:34 pm
by ron350
Thanks for the reply not many members left in this section.
I replaced the CPS because the motor would randomly cut off and the tach would barely move when cranking. When the motor would decide to run I removed the fuel and ignition relays and cranked the car. With the relays removed the tach would read between 1000 and 1500 RPM.
The battery was unhooked from start to finish over a week.

Re: Guess I need case learn?

Posted: Mon Apr 04, 2016 3:23 pm
by Archon
Using the GM SPO servicing information disk, I could find no reference to your engine needing a CASE learn after replacing that sensor. It was not part of the repair instructions (which it is for the 2000), nor could I find any reference with a search.

Re: Guess I need case learn?

Posted: Mon Apr 04, 2016 4:53 pm
by ron350
Thanks Archon that’s what I needed to know.
The car is running good with no codes or stalling so far.

Re: Guess I need case learn?

Posted: Tue Apr 05, 2016 12:10 am
by CMNTMXR57
I don't see it in the procedure either. And P1336 isn't listed for your '96 BTW.

Just out of curiosity, after torquing the harmonic balancer bolt to 110 lb/ft did you then degree it 76*?

Re: Guess I need case learn?

Posted: Tue Apr 05, 2016 2:03 pm
by ron350
I reused the factory balancer bolt and used a drop of blue locktite and torked to 180 ft. lbs. I am not going to risk breaking the bolt with that 76 degrees rotation past 111 ft. lb.

Re: Guess I need case learn?

Posted: Wed Apr 06, 2016 10:58 am
by CMNTMXR57
I agree it's a little silly sometimes... Just give a total torque spec and call it a day. However, GM loves to do it, particularly on TTY bolts (mostly headbolts fall into this category, but others too, such as harmonic balancer bolts and such too).

Re: Guess I need case learn?

Posted: Wed Apr 06, 2016 11:08 am
by SSEBonne4evr
ron350 wrote:Thanks Archon that’s what I needed to know.
The car is running good with no codes or stalling so far.
That is all I was asking you. Thank you.

I also do not see that code listed in the FSM.
Fewer people on this forum every day.