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sprinkles08
sprinkles08, ASE Certified Technician
Category: GMC
Satisfied Customers: 21586
Experience:  ASE Master and Advanced level certified. Factory trained with 15 years dealership experience
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I have a 2007 gmc sierra vortex max which is giving the code

Customer Question

i have a 2007 gmc sierra vortex max which is giving the code p0011. I have flushed and changed the oil, replaced the cmp sensor, cmp magnet, cmp actuator. i just recently got a j2534 connector so that i could use tech2win and with it view the cmp data. The data shows that cmp magnet and sensor work properly until the engine gets up to running temperature, then the cmp command signal starts to flip between 45% to 9% and the cmp senor shows that the actual cmp degrees are 0. what would cause this
Submitted: 6 months ago.
Category: GMC
Expert:  Pete replied 6 months ago.

Hi my name is ***** ***** I will be happy to assist with this today.In some cases I may need more info to assist better.I apologize for any delay.

In some cases this can be an issue with the CMP wiring or connections leading from the CMP sensor to the ECM.I would check and make sure all wiring and connections are o.k. as the ECM is looking for a certain resistance signal and if it doesnt see it then it can cause this code,temp can affect poor wiring or connections as well.I have also seen issues with the ECM itself in some cases to where it needed replaced for this code here.If you want I can post the diagnostics for this code if you want to follow them to see if you can pinpoint what component is causing this issue here just let me know.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service.You can rate at any time and we can continue to work on your question as this will not close out your question.Keep in mind in some cases it can be difficult to fully diagnose or help repair your vehicle without seeing it and I work on delivering the best possible answer from what I see to work with.

Thanks Pete

Customer: replied 6 months ago.
i have checked the wiring as well as replaced the harness from the cmp magnet to the first connection. i have changed out the ecm with a used one but the same issue still came up.
Expert:  Pete replied 6 months ago.

Would you like me to post the diagnostic procedure on this here at all for you to follow to locate the fault?Let me know,thanks Pete.

Customer: replied 6 months ago.
sure ill see if it is the one that i have already followed or not
Expert:  Pete replied 6 months ago.

Here is what I show for this code here on this year and model.

P0011

Important: Incorrect engine oil viscosity, aftermarket engine oil additives, or engine oil that overdue for changing, can greatly affect the performance of the camshaft actuator.

1. Ignition OFF, disconnect C112.
2. Test for less than 1 ohm of resistance between the low reference circuit ECM side, terminal E and ground.

◊If greater than 1 ohm, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.

3. Remove the water pump from the engine.
4. Inspect and test the remaining wire harness from C112 to the CMP solenoid for an open/high resistance, or a short to ground.

◊If the circuit tests normal, perform the component testing for the CMP actuator solenoid.
◊If the CMP solenoid and the circuit test normal, then refer to Camshaft Position Actuator Magnet Cleaning and Inspection and Camshaft Position Actuator Solenoid Valve Inspection (On-Vehicle) Camshaft Position Actuator Solenoid Valve Inspection (Off-Vehicle).

Component Testing

Important: You must perform the Circuit/System Testing before proceeding with Component Testing.

Static Test

Test for 5.9-6.9 ohms of resistance at 20°C, or 68°F between the solenoid control terminal 2 and the low reference terminal 1 at the CMP actuator solenoid.

If the resistance is not with in the specified range, then replace the CMP actuator solenoid. Refer to Camshaft Position Actuator Magnet Replacement.

Dynamic Test

Important: Do not allow electrical current to flow through the CMP actuator solenoid for more than 1-2 seconds, or damage to the solenoid may occur.

Point the CMP actuator solenoid vertically, towards a shop towel. Connect one end of a fused jumper wire to the CMP actuator solenoid control circuit terminal 2 and 12 volts. Connect a second jumper wire to the low reference circuit terminal 1 and momentarily connect to ground. The CMP actuator solenoid should immediately extend.

If the CMP actuator solenoid pintle does not extend, then replace the CMP actuator solenoid. Refer to Camshaft Position Actuator Magnet Replacement.

Diagnostic Aids

This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test. See: Starting and Charging > Component Tests and General Diagnostics > Battery Inspection/Test

Circuit/System Verification

1. Observe the engine oil level. The engine oil level should be within the operating range on the oil indicator stick.
2. Start the engine. Allow the engine to reach normal operating temperature.
3. Monitor the engine oil pressure parameter value with the scan tool. The engine oil pressure must be at or above the minimum hot oil pressure values. Refer to Engine Mechanical Specifications (RPO LY5 VIN J) Engine Mechanical Specifications (RPO LC9 VIN 3) Engine Mechanical Specifications (RPO LY2 VIN C) Engine Mechanical Specifications (RPO LH6 VIN M) Engine Mechanical Specifications (RPO LMG VIN 0) Engine Mechanical Specifications (RPO LY6 VIN K) Engine Mechanical Specifications (RPO L76 VIN Y) Engine Mechanical Specifications (RPO L92 VIN 8).
4. Using the output control function of the scan tool, command the CMP actuator solenoid to 25 degrees. The CMP Desired parameter value should match the CMP Angle parameter value.
5. Observe the CMP Variance value, on the scan tool. The CMP Variance value will increment for several seconds, until the CMP Angle value matches the Desired CMP value. The CMP Variance value should then return to 0 degrees.

◊If the vehicle passes the Circuit/System Verification, then operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that are captured in the Freeze Frame/Failure Records Data list.

Let me know if you need anything else and feel free to rate my help here as this is how I receive credit for my time.

Thanks Pete

Customer: replied 6 months ago.
I have done this process and when i found that the cmp magnet was reading 7.9ohms i replaced it the ecm does read less then 1 ohm between the low reference and ground with the engine off but i did notice that the reading for this was not less then 1 ohm for about 2 seconds after the key was turned off
the oil pressures where well within the parameters
I have used the scan tool to activate the cmp magnet and this works when it is off the vehicle
when i operate the vehicle to the point of setting the dtc that is when i notice that the cmp command starts to flip between 45 % and 9% and the actual cmp angle is 0
Expert:  Pete replied 6 months ago.

Unfortunately this is all of the info I have on this here myself but others here may be able to assist further.

I will open your question up for others here to see if someone else can assist further on this as there may be others here that may have more info on what to check or do with this issue.I hope you can get this resolved with ease.No need to reply to my last post here unless it is a last resort as it will keep your question locked to me and others will not be able to view it.If you feel you want to continue to work with me on this feel free to reply at any time but keep in mind in some cases it can be difficult to fully diagnose or help repair this without seeing your vehicle.

Thanks Pete

Expert:  sprinkles08 replied 6 months ago.

Hello and welcome to JustAnswer!

Do you still need help?

Customer: replied 6 months ago.
but I won't be able to respond for a few hours
Expert:  sprinkles08 replied 6 months ago.

Has the cam actuator wiring been load tested as well as checked for shorts to power, ground or other circuits?

Customer: replied 6 months ago.
I have checked the short to ground on both. No to the short to b+ or other circuits but I have checked the entire length of the wire from the ecm to the camp actuator. I have also checked using a scan tool to activate the cmp actuator with it off the engine to see if the ecm actually sends a signal to it and it does but I haven't load tested it.
Expert:  sprinkles08 replied 6 months ago.

The next thing that should be done is load test the circuits, test them for a short to power, ground and other circuits.

Customer: replied 6 months ago.
How would I do a load test
Expert:  sprinkles08 replied 6 months ago.

You would disconnect the ECM and the actuator connector, apply power or ground to one end. At the other end you would use jumper wires and a headlamp bulb to load the circuit and see that the bulb lights as brightly as if connected to the battery. IF it's dim or doesn't light then you have an issue in the wire.

Customer: replied 6 months ago.
OK I'll check that out later after work and see what happens and get back to you.
Expert:  sprinkles08 replied 6 months ago.

Great!

Customer: replied 6 months ago.
I checked for shorts to ground and b+ as well as shorts to other circuits. All tests negative. I also load tested the circuit and found that there where no issues with the lines. I have since road tested the truck while running the scan tool. It seems that the issue with the cmp actuator goes away in certain circumstances. When I have the accelerator in a certain position ( didn't look to see what percentage). I'm wondering if the MAF has anything to do with this and maybe there is an electrical issue with it
Expert:  sprinkles08 replied 6 months ago.
Do you have the ability to actuate it with a scan tool with the engine off?
Customer: replied 6 months ago.
Are you talking about the cmp because yes I can actuate it with my scan tool
Expert:  sprinkles08 replied 6 months ago.

If you clear the code and actuate the cam actuator with the engine off does the code set?

Customer: replied 6 months ago.
I have done that and no it doesn't set the code
Expert:  sprinkles08 replied 6 months ago.

Where did the replacement actuator come from?

Customer: replied 6 months ago.
Gmc
Expert:  sprinkles08 replied 6 months ago.

Are you able to see cam/crank difference degrees?

Customer: replied 6 months ago.
No I'm not able to see the difference in degrees between them.
Expert:  sprinkles08 replied 6 months ago.

Do you know if the problem started after any work was done?
Is there any abnormal engine noise?

Customer: replied 6 months ago.
I bought the truck at an auction so I don't have any history on it but the only thing that I can tell is that the previous owner neglected it. The motor sounds great with no knocking or anything.
Expert:  sprinkles08 replied 6 months ago.

Have you tested oil pressure?

Customer: replied 6 months ago.
I haven't tested the oil pressure with a mechanical gauge but I thought that the oil pressure was an issue and I replaced th oil pump with a new one right from gm. I'm using tech2win for a scan tool and so I have checked the pressure with it and it shows the pressure within the parameters set out in the manual
Expert:  sprinkles08 replied 6 months ago.

What pressure was shown with the engine at operating temperature idling in gear?

Customer: replied 6 months ago.
16 psi
Expert:  sprinkles08 replied 6 months ago.

I'm a full time tech and at work this morning, I'll get back to you as quickly as I can!

Expert:  sprinkles08 replied 6 months ago.

That's pretty low and you're probably under spec, definitely low enough to cause this issue. What do you see at 2,000 RPM hot?

Customer: replied 6 months ago.
Here are the specs if I'm reading them properly
Expert:  sprinkles08 replied 6 months ago.

Those specifications aren't correct per the factory service information. What do you see at 2,000 RPM?

Customer: replied 6 months ago.
35 psi
Expert:  sprinkles08 replied 6 months ago.

That's right on the minimum and shoudl be low enough to cause the issue you're having. Either way, the problem is internal in the engine. The problem is either being caused by the low oil pressure or a timing chain/gear issue.

Customer: replied 6 months ago.
I was wondering if the timing chain could cause this. I will have to check the oil pressure with a mechanical gauge before I go deeper into whether or not it is a pressure issue or not.
Expert:  sprinkles08 replied 6 months ago.

Yes, the timing chain cam cause this. This code sets when either there is a circuit issue with the cam actuator or the cam/crank sync doesn't respond correctly to cam position changes.