Crankshaft Position Sensor Error P1336
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Heel & Toe
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Crankshaft Position Sensor Error P1336
I have a 2001 with a Magnuson supercharger. The engine beneath the blower is stock. Recently, I went to a car show and when I pulled in the car was fine. When I started it to leave I got a check engine light. I scrolled through the error codes and found a P1336HC code which I believe is a cranshaft position sensor error. The car ran fine for the 20 mile drive home. Someone said that there is a possibility that oil or grass (I was parked in the grass) interfered with the signal when the engine started and may have caused this error. I am not an expert with the CPS so I am not sure how to take this. Is there an external sensor on the front of the engine that can get "dirty" and cause the error or is the CPS measuring timing etc internally on the crankshaft? Thanks
Last edited by lt1z123; Jun 9, 2009 at 04:30 PM.
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Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
DTC P1336
Circuit Description
The crankshaft position (CKP) sensor sends pulses to the powertrain control module (PCM) when the reluctor wheel teeth rotate past the CKP sensor. The PCM uses the CKP pulses in order to synchronize the ignition and the fuel injector operation, and in order to time the interval between each CKP pulse. The PCM determines when an excessive change in the 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 or 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:
The crankshaft
The reluctor wheel
The 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.
After the following actions, perform the learning procedure:
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.
Important
A PCM power disconnect with the ignition ON may erase the stored pulse value and may set the DTC P1336.
Disconnecting the PCM will not erase the learned crankshaft position system variation as long as the ignition switch is in the OFF position.
Important
Reprogramming the PCM does not require running the crankshaft position system variation learn procedure unless the PCM is new or is from another vehicle.
A DTC P1336 sets if the crankshaft position system variation is not within an acceptable range, or cannot be learned.
Conditions for Running the DTC
DTCs P0335, P0336, P0341, P0342, and P0343 are not set.
Conditions for Setting the DTC
The PCM has not learned the crankshaft position system variation.
Action Taken When the DTC Sets
The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.
Conditions for Clearing the MIL/DTC
The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.
Diagnostic Aids
Important
Before you service the PCM, remove any debris from the PCM connector surfaces. Inspect the PCM connector gaskets when you diagnose or replace the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM.
For any test that requires probing the PCM or probing a component harness connector, use the J 35616-A connector test adapter kit. Using this kit prevents damage to the harness and component terminals. Refer to Using Connector Test Adapters in Wiring Systems. If the PCM receives an incorrect crankshaft-to-camshaft ratio, the PCM will not allow the scan tool to enable the learn procedure.
If the crankshaft position system variation learn procedure cannot be learned, inspect for the following conditions:
A chipped or damaged reluctor wheel
Incorrect alignment of the CKP sensor to the reluctor wheel
Excessive crankshaft run-out
Interference in the signal circuit to the CKP sensor
Incorrect ratio of crankshaft to camshaft pulses
The engine diagnostic misfire is not operable when the engine is above 1,000 RPM and DTC P1336 is set.
When the learn procedure is in progress and the engine speed is at 4,000 RPM, a decrease in the engine speed will occur. During the engine coastdown, the PCM monitors the CKP sensor signal and stores the pattern. This pattern is used in order to determine if the crankshaft speed variations are due to misfire.
For an intermittent condition, refer to Intermittent Conditions .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
The PCM enables the learn process after 65°C (150°F) is reached. Engine deceleration occurs when the learn procedure is in progress. The PCM monitors and records the CKP sensor signal during engine coast-down conditions.
Test in Progress status on the scan tool indicates the PCM is performing the learn procedure. If the PCM receives any of the signals listed below, the learn procedure will not be allowed.
An incorrect crankshaft-to-camshaft pulse ratio
An incorrect transmission range signal input
Corrupted communication
No change in the brake switch input
If a repair is necessary due to a condition which prevented the learn procedure from enabling, the crankshaft position system variation learning Procedure must be performed.
The ignition must be in the OFF position for at least 10 seconds after the learn procedure is complete, and after the engine RPM has returned to idle. The PCM saves the signal data after these conditions are met.
Step
Action
Value(s)
Yes
No
1
Did you perform the Diagnostic System Check-Engine Controls?
--
Go to Step 2
Go to Diagnostic System Check - Engine Controls
2
Perform the crankshaft position system variation learning procedure as follows.
Install the scan tool.
Apply the vehicle's parking brake.
Block the drive wheels.
Close the hood.
Place the vehicle's transmission in PARK if the vehicle has an automatic transmission, or in NEUTRAL if the vehicle has a manual transmission.
Idle the engine until the specified engine coolant temperature value is reached.
Turn OFF all the accessories.
Apply the brakes for the duration of the procedure.
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 will respond to throttle position after the learn procedure is complete.
Enable the crankshaft position system variation learning procedure with the scan tool.
Slowly raise the engine RPM to the specified value.
Immediately release the throttle when the engine speed decreases.
Does the scan tool indicate Learn Status: Learned This Ignition?
65°C (150°F)
4000 RPM
Go to Step 5
Go to Step 3
3
Attempt the crankshaft position system variation learn procedure as many times as the specified value. Refer to CKP System Variation Learn Procedure .
Does the scan tool indicate Learn Status: Learned This Ignition?
3
Go to Step 5
Go to Step 4
4
Inspect the crankshaft position (CKP) sensor and the crankshaft reluctor wheel for damage. Refer to Diagnostic Aids.
Did you find any damage?
--
Go to Step 6
Go to Diagnostic Aids
5
Turn OFF the ignition for 15 seconds.
Is the action complete?
--
Go to Step 7
--
6
Replace the crankshaft position (CKP) sensor and/or reluctor wheel. Refer to Crankshaft Position (CKP) Sensor Replacement .
Is the action complete?
--
Go to Step 7
--
7
Use a scan tool in order to clear the DTCs.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC run and pass?
--
Go to Step 8
Go to Step 2
8
With a scan tool, observe the stored information, Capture info.
Does the scan tool display any DTCs that you have not diagnosed?
--
Go to Diagnostic Trouble Code (DTC) List
System OK
--------------------------------------------------------------------------------
Document ID# 722000
2001 Chevrolet/Geo Corvette
Circuit Description
The crankshaft position (CKP) sensor sends pulses to the powertrain control module (PCM) when the reluctor wheel teeth rotate past the CKP sensor. The PCM uses the CKP pulses in order to synchronize the ignition and the fuel injector operation, and in order to time the interval between each CKP pulse. The PCM determines when an excessive change in the 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 or 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:
The crankshaft
The reluctor wheel
The 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.
After the following actions, perform the learning procedure:
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.
Important
A PCM power disconnect with the ignition ON may erase the stored pulse value and may set the DTC P1336.
Disconnecting the PCM will not erase the learned crankshaft position system variation as long as the ignition switch is in the OFF position.
Important
Reprogramming the PCM does not require running the crankshaft position system variation learn procedure unless the PCM is new or is from another vehicle.
A DTC P1336 sets if the crankshaft position system variation is not within an acceptable range, or cannot be learned.
Conditions for Running the DTC
DTCs P0335, P0336, P0341, P0342, and P0343 are not set.
Conditions for Setting the DTC
The PCM has not learned the crankshaft position system variation.
Action Taken When the DTC Sets
The control module illuminates the malfunction indicator lamp (MIL) when the diagnostic runs and fails.
The control module records the operating conditions at the time the diagnostic fails. The control module stores this information in the Freeze Frame/Failure Records.
Conditions for Clearing the MIL/DTC
The control module turns OFF the malfunction indicator lamp (MIL) after 3 consecutive ignition cycles that the diagnostic runs and does not fail.
A current DTC, Last Test Failed, clears when the diagnostic runs and passes.
A history DTC clears after 40 consecutive warm-up cycles, if no failures are reported by this or any other emission related diagnostic.
Clear the MIL and the DTC with a scan tool.
Diagnostic Aids
Important
Before you service the PCM, remove any debris from the PCM connector surfaces. Inspect the PCM connector gaskets when you diagnose or replace the PCM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminate intrusion into the PCM.
For any test that requires probing the PCM or probing a component harness connector, use the J 35616-A connector test adapter kit. Using this kit prevents damage to the harness and component terminals. Refer to Using Connector Test Adapters in Wiring Systems. If the PCM receives an incorrect crankshaft-to-camshaft ratio, the PCM will not allow the scan tool to enable the learn procedure.
If the crankshaft position system variation learn procedure cannot be learned, inspect for the following conditions:
A chipped or damaged reluctor wheel
Incorrect alignment of the CKP sensor to the reluctor wheel
Excessive crankshaft run-out
Interference in the signal circuit to the CKP sensor
Incorrect ratio of crankshaft to camshaft pulses
The engine diagnostic misfire is not operable when the engine is above 1,000 RPM and DTC P1336 is set.
When the learn procedure is in progress and the engine speed is at 4,000 RPM, a decrease in the engine speed will occur. During the engine coastdown, the PCM monitors the CKP sensor signal and stores the pattern. This pattern is used in order to determine if the crankshaft speed variations are due to misfire.
For an intermittent condition, refer to Intermittent Conditions .
Test Description
The numbers below refer to the step numbers on the diagnostic table.
The PCM enables the learn process after 65°C (150°F) is reached. Engine deceleration occurs when the learn procedure is in progress. The PCM monitors and records the CKP sensor signal during engine coast-down conditions.
Test in Progress status on the scan tool indicates the PCM is performing the learn procedure. If the PCM receives any of the signals listed below, the learn procedure will not be allowed.
An incorrect crankshaft-to-camshaft pulse ratio
An incorrect transmission range signal input
Corrupted communication
No change in the brake switch input
If a repair is necessary due to a condition which prevented the learn procedure from enabling, the crankshaft position system variation learning Procedure must be performed.
The ignition must be in the OFF position for at least 10 seconds after the learn procedure is complete, and after the engine RPM has returned to idle. The PCM saves the signal data after these conditions are met.
Step
Action
Value(s)
Yes
No
1
Did you perform the Diagnostic System Check-Engine Controls?
--
Go to Step 2
Go to Diagnostic System Check - Engine Controls
2
Perform the crankshaft position system variation learning procedure as follows.
Install the scan tool.
Apply the vehicle's parking brake.
Block the drive wheels.
Close the hood.
Place the vehicle's transmission in PARK if the vehicle has an automatic transmission, or in NEUTRAL if the vehicle has a manual transmission.
Idle the engine until the specified engine coolant temperature value is reached.
Turn OFF all the accessories.
Apply the brakes for the duration of the procedure.
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 will respond to throttle position after the learn procedure is complete.
Enable the crankshaft position system variation learning procedure with the scan tool.
Slowly raise the engine RPM to the specified value.
Immediately release the throttle when the engine speed decreases.
Does the scan tool indicate Learn Status: Learned This Ignition?
65°C (150°F)
4000 RPM
Go to Step 5
Go to Step 3
3
Attempt the crankshaft position system variation learn procedure as many times as the specified value. Refer to CKP System Variation Learn Procedure .
Does the scan tool indicate Learn Status: Learned This Ignition?
3
Go to Step 5
Go to Step 4
4
Inspect the crankshaft position (CKP) sensor and the crankshaft reluctor wheel for damage. Refer to Diagnostic Aids.
Did you find any damage?
--
Go to Step 6
Go to Diagnostic Aids
5
Turn OFF the ignition for 15 seconds.
Is the action complete?
--
Go to Step 7
--
6
Replace the crankshaft position (CKP) sensor and/or reluctor wheel. Refer to Crankshaft Position (CKP) Sensor Replacement .
Is the action complete?
--
Go to Step 7
--
7
Use a scan tool in order to clear the DTCs.
Turn OFF the ignition for 30 seconds.
Start the engine.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC run and pass?
--
Go to Step 8
Go to Step 2
8
With a scan tool, observe the stored information, Capture info.
Does the scan tool display any DTCs that you have not diagnosed?
--
Go to Diagnostic Trouble Code (DTC) List
System OK
--------------------------------------------------------------------------------
Document ID# 722000
2001 Chevrolet/Geo Corvette
