My first instinct is that the P0336 code - crankshaft position sensor - explains most of it. For sure, if the computer loses track of where the crankshaft is, a misfire is certainly possible. It's not clear if that might somehow also cause the P0011 - I don't have experience with that.
The P0336 could be due to a bad crankshaft position sensor, or maybe a wiring issue. My next step would be to inspect the wiring to the two sensors - make sure the connectors are fully seated, and that the wires are not damaged. Also inspect the wiring to the camshaft actuator to be sure it's in good condition.
If the wires are OK, I would probably put in a new crankshaft position sensor. It's a pain to get at, but do-able. After that, if the codes don't come back, you're done. Otherwise, you'll have to pursue the P0011 further.
The P0011 means the computer "has determined that the bank 1 intake camshaft is more advanced than what the ECM has commanded it be" according to Google. Is that because the actuator didn't move it, or because the sensor is reading it wrong? So, if the P0011 persists, further diagnosis is required.
Just as the crankshaft position sensor failing can cause the engine to run poorly, so too can the cam timing being off.
But multiple, simultaneous failures are not that common. So when multiple codes pop up, it's often due to a wiring issue, or due to one failure causing multiple related codes.
I no longer have a 3.5L motor, so I can't go study it. But as I recall, there is only one cam (in the block), and hence only one camshaft sensor. As I sit here drinking coffee still half asleep, it's not clear how a bad crankshaft sensor can somehow also trigger a P0011 unless they share some common wiring which has become damaged. So that's why I would inspect the wiring to both sensors first.
Crankshaft position sensors are in the 30-40 dollar range at Autozone. Camshaft position sensors are in the 25-45 range. The camshaft actuators are a bit more pricey, in the range 95-160 dollars.
Regarding an oil leak affecting a sensor, externally, a leak could affect the wiring, causing a bad signal. Inspecting the wires will show if that's the case. Internally, the crankshaft position sensor lives in oil, so that's not an issue.
HTH.
Doug
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