New ECm installed and code PO315 will not clear. Crankshaft position system variation not learned. What should I do?

Did you do a
Crankshaft Position System Variation Learn ?
The crankshaft position system (CKP) variation compensating values are stored in the powertrain control module (PCM) non-volatile memory after a learn procedure has been performed. If the actual crankshaft position system variation is not within the crankshaft position system variation compensating values stored in the PCM, DTC P0300 may set, refer to Diagnostic Aids for DTC P0300 .
The Crankshaft Position System Variation Learn Procedure should be performed if any of the following conditions are true:
• DTC P1336 is set
• The PCM has been replaced
• The engine has been replaced
• The crankshaft has been replaced
• The crankshaft harmonic balancer has been replaced
• The crankshaft position sensor has been replaced

DTC P0315 Crankshaft Position (CKP) System Variation Not Learned
The crankshaft position (CKP) system variation learn feature is used to calculate reference period errors caused by slight tolerance variations in the crankshaft, and the crankshaft position sensors. The calculated error allows the powertrain control module (PCM) to accurately compensate for reference period variations. This enhances the ability of the PCM to detect misfire events over a wider range of engine speed and load. The PCM stores the crankshaft position system variation values after a learn procedure has been performed. If the actual crankshaft position variation is not within the crankshaft position system variation compensating values stored in the PCM, DTC P0300 may set. If the PCM detects the CKP system variation values are not stored in the PCM memory, DTC P0315 sets.
you need a factory scan tool to do the variation relearn .
Install a scan tool.
Monitor the engine control module (ECM) for DTCs with a scan tool. If other DTCs are set, except DTC P0315, refer to Diagnostic Trouble Code (DTC) List - Vehicle for the applicable DTC that set.
With a scan tool, select the CKP system variation learn procedure and perform the following:
3.1. Observe the fuel cut-off for the applicable engine.
3.2. Block the drive wheels.
3.3. Set the parking brake.
3.4. Place the vehicle's transmission in Park or Neutral.
3.5. Turn the air conditioning (A/C) OFF.
3.6. Cycle the ignition from OFF to ON.
3.7. Apply and hold the brake pedal for the duration of the procedure.
3.8. Start and idle the engine.
3.9. Accelerate to wide open throttle (WOT). The engine should not accelerate beyond the calibrated fuel cut-off RPM value noted in step 3.1. Release the throttle immediately if the value is exceeded.

Important: While the learn procedure is in progress, release the throttle immediately when the engine starts to decelerate. The engine control is returned to the operator and the engine responds to throttle position after the learn procedure is complete.
3.10. Release the throttle when fuel cut-off occurs.
The scan tool displays Learn Status: Learned this Ignition. If the scan tool indicates that DTC P0315 ran and passed, the CKP variation learn procedure is complete. If the scan tool indicates DTC P0315 failed or did not run, refer to DTC P0315 . If any other DTCs set, refer to Diagnostic Trouble Code (DTC) List - Vehicle for the applicable DTC that set.
Turn OFF the ignition for 30 seconds after the learn procedure is completed successfully.

Did you replace the crank sensor ?

Only has one crankshaft position sensor ,an cam sensors . To change the crank sensor u would have to pull the starter ,located above starter .
Camshaft Position Sensor Replacement - Intake Camshaft Position Sensor Replacement - Exhaust
After a crank sensor replacement a
Crankshaft Position System Variation Learn has to be done !
Important: The crankshaft position (CKP) system variation learn procedure is required when the following service procedures have been performed, regardless of whether DTC P0315 is set:
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Engine replacement

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Engine control module (ECM) replacement

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Crankshaft damper replacement

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Crankshaft replacement

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CKP sensor replacement

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Any engine repairs which disturb the crankshaft to CKP sensor relationship

Important: The scan tool monitors certain component signals to determine if all the conditions are met to continue with the CKP system variation learn procedure. The scan tool only displays the condition that inhibits the procedure. The scan tool monitors the following components:
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CKP sensor activity--If there is a CKP sensor condition, refer to the applicable DTC that set.

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Camshaft position (CMP) signal activity--If there is a CMP signal condition, refer to the applicable DTC that set.

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Engine coolant temperature (ECT)--If the engine coolant temperature is not warm enough, idle the engine until the engine coolant temperature reaches the correct temperature.

You best bet is take to a ASE certified repair shop or a GM dealer ! When replacing crank sensor a special procedure has to be done with a scan tool .
Crankshaft Position System Variation Learn
The Crankshaft Position System Variation Learn Procedure should be performed if any of the following conditions are true:
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DTC P1336 is set

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The PCM has been replaced

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The engine has been replaced

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The crankshaft has been replaced

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The crankshaft harmonic balancer has been replaced

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The crankshaft position sensor has been replaced
Important: Set the vehicle parking brake and block the drive wheels when performing the crankshaft position system variation learn procedure in order to prevent personal injury. Release the throttle when the engine reaches the SECOND fuel cut off. Leaving the throttle open during the fuel cut-off will allow the engine to decel at an even rate. Once the learn procedure is completed, the PCM will return the engine control to the operator and the engine will respond to the throttle position.
Important: The scan tool crankshaft position system variation learn function will be inhibited if engine coolant temperature is less than 70?°C (158?°F). Allow the engine to warm to at least 70?°C (158?°F) before attempting the crankshaft position system variation learn procedure.
The scan tool crankshaft position system variation learn function will be inhibited if any powertrain DTCs other than DTC P1336 are set before or during the crankshaft position system variation learn procedure. Diagnose and repair any DTCs if set.
The crankshaft position system variation learn function will be inhibited if the PCM detects a malfunction involving the camshaft position signal circuit, the 3X reference circuit, or the 18X reference circuit.
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If the scan tool indicates a problem with the cam signal, refer to DTC P0341 .

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If the scan tool indicates a problem with the 3X crank signal, refer to DTC P1374 .

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If the scan tool indicates a problem with the 18X crank signal, refer to DTC P0336 .

Now why do you want to replace these thing's ? mite be able to save you some time an money. Do you have a check engine light lit ? Codes ? Does it start an run ?

My info says it is located above the starter motor. Info says to remove the starter.

The info also says you have to do a crankshaft variation relearn procedure. I can't help you with that procedure.

Definition of Diagnostic Trouble Code P0300 Category: Powertrain Definition: Random/Multiple Cylinder Misfire Detected

Definition of Diagnostic Trouble Code P0315 Category: Powertrain Definition: Crankshaft Position System Variation Not Learned

Definition of Diagnostic Trouble Code P0339 Category: Powertrain Definition: Crankshaft Position Sensor "A" Circuit Intermittent

you can read through the suggested answers and you can read through this discussion to get insight into the problem. Dodge Codes P0315 and P0339

The following service procedures require either a programming or a setup event performed for a complete repair.
ECM Replacement
Important: It is not necessary to program a new engine control module (ECM). The ECM is programmed from the factory. Ensure the new ECM is equipped with the latest software/calibration.
If the engine control module (ECM) is replaced, the following procedures must be performed:
Idle Learn Procedure--Refer to the appropriate procedure:
• Idle Learn for the 1.4L DOHC engine
• Idle Learn for the 1.4L SOHC engine
• Idle Learn for the 1.6L engine
The crankshaft position (CKP) System Variation Learn Procedure-- Refer to the appropriate procedure:
• Crankshaft Position System Variation Learn for the 1.4L DOHC engine
• Crankshaft Position System Variation Learn for the 1.4L SOHC engine
• Crankshaft Position System Variation Learn for the 1.5L engine
• Crankshaft Position System Variation Learn for the 1.6L engine
Theft Deterrent--Refer to Programming Theft Deterrent System Components . The ECM will learn the incoming fuel continue password immediately upon receipt of a password message. Once a password message is received, and a password is learned, a learn procedure must be performed to change this password again. An ECM which has been previously installed in another vehicle will have learned the other vehicle's fuel continue password, and will require a learn procedure after programming to learn the current vehicle's password.

Hi Simon,here's a link to your code. Toyota P0315 OBD DLC Error Code Crankshaft Position System Variation Not...

P1335 CHEVROLET P1335 CHEVROLET - Crankshaft Position Circuit Possible causes
- Faulty Crankshaft Position Sensor
- Crankshaft Position (CKP) Sensor harness is open or shorted
- Crankshaft Position (CKP) Sensor circuit poor electrical connection Help with this
Symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
- Lack/Loss of Power
- Engine Stall
P1335 CHEVROLET Description
The Crankshaft Position (CKP) sensor sends pulses to the Powertrain Control Module (PCM) as the reluctor wheel teeth rotate past the CKP sensor. The PCM uses the CKP pulses to synchronize the ignition and fuel injector operation, and to time the interval between each CKP pulse. The PCM determines when an excessive change in crankshaft speed occurs by comparing each new time interval with the previous interval. A misfire causes an unexpected change in the crankshaft speed. A certain amount of acceleration/deceleration is expected between each firing stroke, but if the crankshaft speed changes more than an expected amount, the PCM interprets this as a misfire. The interval between CKP sensor pulses is extremely small. At high engine speeds, slight variations in the following components make misfire detection difficult:
- Crankshaft
- Reluctor wheel
- CKP sensor
The PCM learns variations during the Crankshaft Position System Variation Learning Procedure. The PCM compensates for these variations when performing detect misfire calculations. Only a scan tool can command the PCM to perform the Crankshaft Position System Variation Learning Procedure again.
Perform the learning procedure after the following actions:
- A PCM replacement
- Any operation or repair involving the crankshaft, the CKP sensor, or the CKP sensor to reluctor wheel gap relationship.
- An engine replacement.
- The ignition switch is in the ON position until the battery is drained.


Read more: http://nissanhelp.com/diy/obd_codes/p1335_chevrolet.html#ixzz37IoD1Imx