Lack of Power up hills or highway. 2003 Nissan Pathfinder.

[nWoStyle]

I have a 2003 Nissan Pathfinder with 186,000 km that I bought from an Auction. It ran fine for several months then I noticed that the car had problems accelerating up hills, making sudden left turns or doing anything that required putting a load on the engine.
Driving downhill or on flat surfaces the car was fine. Car would routinely go at 30-40km up hills even when when pressing down fully on the accelerator. The RPMs go extremely high, but the car doesn't go any faster or just marginally increases in speed. This of course is extremely dangerous on the highway.
The code that came up was P0021 and P0011 which says is for the Intake Timing Control Solenoid valve (Bank 2 and Bank 1 respectively).
So far I had the CAM sensors replaced, the solenoid valves cleaned (both banks), a hot oil flush done, and engine purge run through the oil before changing the oil. None of them seem to work. What do you think?

[nWoStyle]

Hi. does anybody else have the same problem or can help me out?
Usually this error code comes up when oil is low or dirty, but it still occurs with new oil at the proper level.
I've had the sensors replaced and the the solenoids replaced, so it wasn't that... anything else to try?

[smj999smj]

Those codes were somewhat common on the VQ35DE. Unfortunately, diagnosing them is pretty difficult, even with a scantool. They usually tend to be caused by either bad variable intake timing position actuators or bad variable intake timing position sensors, with the actuators being the more common failure. Dorman products even offers them on the aftermarket.