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Anytime there is blue smoke, oil is being burned. However, why only when warm? There are several things that can cause this. First, I would check engine compression. If there is a weak cylinder, do the test "Wet".
See picture 3 for the manufacturer's specs.
A wet test is done on a cylinder with low compression. About a table spoon of oil is put into the cylinder. If compression increases, the problem is with the rings. If it doesn't, it could be a valve issue, head gasket, or something is cracked.
Now, other things that can cause this is oil drainage from the valve cover area (top of head) is draining too slowly back into the oil pan. If excessive oil builds up, the valve seals cannot stop some from getting by and being burned in the cylinders.
To check this, remove the valve cover and inspect the oil drains in the head. Make sure oil can flow without interruption. Here is a link that shows how to replace a valve cover gasket. It will provide what is done to remove and replace.
There is a variable valve timing actuator (VVT) which can be an issue. It is located at the end of the camshaft. Here are inspection directions which you can do when you remove the valve cover. Note: If the VVT actuator is not working properly, it will cause engine timing issues which can lead to power loss, noise, or oil consumption.
Here are the basic directions for checking the VVT actuator. See picture 1
VARIABLE VALVE TIMING ACTUATOR INSPECTION [WITH VARIABLE VALVE TIMING MECHANISM]
Variable valve timing actuator cannot be disassembled because it is a precision unit.
1. Confirm that the groove of the rotor and notch of the cover at the variable valve timing actuator are aligned and fixed.
If the notch and the bump are not aligned, rotate the rotor toward the valve timing retard position by hand until they are in place.
If the rotor and cover are not fixed even though their notch and groove are aligned, replace the variable valve timing actuator.
If you look at picture 2, it indicates possible causes of excessive oil consumption.
Since you hear a noise and the oil usage goes away, I honestly suspect an issue with the VVT actuator.
I hope this helps. Let me know what you find or if you have other questions.
Images (Click to enlarge)
Thursday, November 15th, 2018 AT 8:46 PM