Equipped with the following engines

2.0L (LNF LHU)

2.2L (L61 LAP LE8)

2.4L (LAT LAF LE5 LE9 LEA LUK) 

Supersession Statement:
This PI was superseded to update Models. Please discard PIP4548F

The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern
Some customers may comment of a Service Engine Soon light being illuminated or a crank no start concern. Upon inspection, DTCs P0016 and/or P0017 will be stored.
This may be the result of a camshaft reluctor that has moved on the camshaft. The reluctor is a press fit and is not indexed/keyed to the camshaft, it is an interference type fit. An overheat condition may contribute to the concern, causing the reluctor to spin/shift on the camshaft when hot.  If the reluctor spins far enough, it can create a crank no start condition. 

On rare occasions, the engine may crank and not run and not set any codes. 
This could be caused by a camshaft reluctor being spun/shifted or a faulty camshaft position sensor or solenoid. It could also be caused by a faulty mass air flow sensor.

Recommendation/Instructions
DTC's P0016 and/or P0017 will be stored and engine may or may not run.
Important: The procedure below was developed for 2006 and newer 2.4L LE5 engines. The reluctor position on other engine RPOs may vary. As a result, it may be necessary to compare the reluctor position of other engine RPOs to a known good engine with the same RPO code.  If the engine is timed properly and SI diagnosis does not isolate the cause of this concern, perform the suggestions below:

To check the Exhaust Cam reluctor position LE5 ONLY:

With the exhaust camshaft positioned so that the valves for #4 cylinder are at maximum lift (fully opened valves), the reluctor should be flush/parallel to the rocker cover gasket surface as shown in the photo below. If the reluctor position does not line up correctly, the exhaust camshaft must be replaced.

To check 


Object ID: 2218883Open In New TabZoom/Print
To check the Intake Cam reluctor position LE5 ONLY:

With the Intake camshaft positioned so that the valves for #1 cylinder are at maximum lift (fully opened valves), the reluctor should be flush/parallel to the rocker cover gasket surface as shown in the photo below. If the reluctor position does not line up correctly, the intake camshaft must be replaced.


Object ID: 2218882Open In New TabZoom/Print
Notice: Each of the procedures above may not detect a small movement in the reluctor, it may be necessary to compare to a known good engine if in doubt. Also note that the cam cover gasket surface does not line up with the same face/slot on the intake and exhaust reluctor.  

Engine cranks but does not run and no codes set. - Unplug one sensor or solenoid and crank the engine to see if it runs. Plug the sensor or solenoid back in and unplug a different one and crank the engine to see if it starts. Perform this procedure for these sensors; intake camshaft position solenoid, exhaust camshaft position solenoid, intake camshaft position sensor, exhaust camshaft position sensor and the mass air flow sensor.  
If the engine cranks and runs with one of the camshaft position solenoids or mass air flow sensor unplugged, then typically that sensor is faulty.

If the engine starts and runs with one of the camshaft position sensors unplugged, then the camshaft position sensor that is unplugged is faulty or the reluctor has spun/shifted for the associated camshaft. Replace the suspect camshaft position sensor or swap the intake and exhaust camshaft position sensors with each other. Note: If the intake and exhaust camshaft position sensors are swapped with each other and the engine starts and runs with both of them plugged in, the camshaft position sensor currently in the intake location is faulty. 

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.

GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer".  They are written to inform these technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle.  Properly trained technicians have the equipment, tools, safety instructions, and know-how to do a job properly and safely.  If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that your vehicle will have that condition.  See your GM dealer for information on whether your vehicle may benefit from the information.

image	
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION

© 2019 General Motors.  All rights reserved.